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Indian Agricultural 
Research Institute, New Delhi. 

IS8o?>A- t$Sc^ 

I. A.R.I.6. 

MGIPC — SI — C AR/ot— 7-7-54— 10,000. 




THE 


Agricultural Journal 

op 

British Guiana 



DEPARTMENT OF AGRICULTURE 
GEORGETOWN 
BRITISH GUIANA. 




Vol. IX, No. i. 


March, 1938. 


The 

Agricultural Journal 

of 

British Guiana 



IS803 

» • 

PUBLISHED BY 

THE DEPARTMENT OF AGRICULTURE, 

GEORGETOWN BRITISH GUIAW 


Price 


M 

»■ 


• a 

• a 


6d. 




DEPARTMENT OF AGRICULTURE. 


ADMINISTRATION 

Director of Agriculture ... ... Prof. The Hon. J. Sydney Dash, 

B.Sc. (AgriM 

Deputy Director ... ... ... F. Burnett, M.C., M.A. 


Clerical 

Senior Clerk 
Registrar of Banks 

Class III Clerks 


Probationers 

Librarian 

RESEARCH BRANCH. 

Botany and Plant Pathology 

Botanist — Plant Pathologist ami Superintend • 
ent. Hot anii : Garden*: 

E. B. Martyn, B A.. A.I.C.T.A. 

T<<h)ttcal A distant : 

X. Porsaud 

Chemistry 

Chemist : 

D, W. Duthie. M.A . B.Sc,, rh.D M F.T.C. 
A ssistant Chemist : 

C. L. C. Bourne 

Entomology 

Entomologist . 

L. D. Clear©, F.R. Ent. S. 

Technical Assistant * 

C. Will nuns 

Rice 

Assistant Plant Brtethr: 

P. A. Ch:m*Clioong, B.Sc., A.T.C T.A. 

Sugar 

(In co-operation with the Sugar Producers) 
Sugar Agronomist and Plant Bncd/r : 

C. H. B. Williams. M.A., A.LC.T.A.. Dip. 
Agr. 1 

Laboratory Assistants : 

H. B. Singh 

A, V. Wan-Piug, Dip. Agr. 

Statistical Clerk : 

J. B. Bourne 


Staff. 

J. F. Irving. M.C. 

W. G. Delph 
( A. A. Thorne 
< Miss X. Green 
( Miss D. M. Terrill 
Miss M. Cheong 
P. O. Jackson 
S. a. Adams 
Miss It. Delph 

Miss V. Chnn-Choong 

LIVESTOCK BRANCH 

Veterinary Surgeon . 

T. Bone, O.B.E . M.R.C.V.S. 

FIELD BRANCH 

Agricultural Superintendent s ■ 

Berbice- .1 D. Gillespie, B.Sc. 

Demerara, East— E.M. Peterkin 
Demerara, East Bank— H. 1). Huggins, 
M.Sc., Dip. Agr. 

Demerara. West — E. G. Benson, B.Sc,, 
A.I.C.T.A.. Dip. Agr. 

Exsequibo A. A. Abraham 
A ssistant Agricultural Superintendent . 

Berbice -E. M. Morgan 
Agricultural Instructors : 

Botanic Gardens- — H. A. Eole 
Demerara, Eaxf-- j C C. Dowding, F L.S , 
] F.R.H.S. 

IW. A. Boveli. 

Demerara. East Bank— I. Dewar (acting) 
Essequibo — A. W. Sears 
Xorth West District — L. E. McKinnon 
Agricultural Assistants : 

Demerara. East — J. Indrobeharry 
Berbice— H. B. France 

Sugar 

Field Manager (Central Station) 

C. Cameron 
Field Assistants : 

L. A. Forte 
B. A. McArthur 



METEOROLOGICAL BRANCH 

Technical Assistant : 

D. D. Blackman 

Meteorological Assistant . 

J. E, Isaac* 


RICE GRADING BRANCH 

Grading Inspector : 

H. E. H. Gadd 

Technical Assistant * : 

G. L. Leitch 
B. R. Ross 


ADVISORY BOARD OF AGRICULTURE 

Director of Agriculture, Chairman, ex officio. 

Deputy Director ot Agriculture, Vice-Chairman, ex officio. 

Hon. Peer Bacchus ... ••• \ 

Hon. R E. Brassing! on ... ••• 1 

Hon. J W Jackson .. ... •• f 

Hon. F. J. Seaford, oji.e ... ... ... > Members 

Mr. S. Andries ... ... ... ... [ 

,. R. B, Hunter ... ... ) 

W. H. Richards ... ... ' 

SUGAR EXPERIMENT STATIONS COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 
Hon. M. B G, Austin 
Mr. J. Bee 
,, G. M. Eccles 
„ J. C. Gibson 
.. A. Murison 
„ R. E. Rhodes 


Georgetown 
Pin. Albion 
Pin. Blairmont 
Pin. Port/Mourant 
Pin. Uitvlugt 
Pin. Diamond 


( Representing 
the Sugar 
Industry 
which main* 
tains the 
J Stations 


CO-OPERATIVE CREDIT BANKS’ BOARD. 


Director of Agriculture, Chairman, ex-officio. 
Dr. the Hon. J. B. Singh ... 

Rev. A. E. Dyett ... 

Mr. 0. Farnum 
„ J. L. Wills .. 


i 

j 


Members 


DISTRICT AGRICULTURAL COMMITTEES 


Director of Agriculture, Chairman 
District Commissioner 
Deputy Director of Agriculture 
Hon. J. I. dc Aguiar 
Hon. E. M. Walcott 
Mr. 8. Andries ... 

„ M. Ghani ... 

„ W. H. Richards 
„ J. E. Wills ... 


EAST DEMERARA 



WEST DEMERARA 

Director of Agriculture, Chairman 
District Commissioner 

Deputy Director of Agriculture ... ] 

Hon. J. W Jackson .. ... .. | 

Dr. the Hon. J. B. Singh ... ... j 

Mr. R. P. Carry 1 ... ... ... i 

„ J.C. DaSilva ... ... ... 

„ R. B. Hunter 
A. Murison ... 

,, W Ramdeholl 
„ A. Rayman ... 


Members 


Members 



CONTENTS. 

(VOL. IX, No. 1.) 


EDITORIAL — Grasses 


Page 

1 


ORIGINAL ARTICLES. 

The Use of Vegetation for 

Coast Protection ... Geiald 0. Caw ... ... ... 4 

Status of the Amazon Fly in 

British Guiana, 1937 ... L, D. Clean, F.R. Ent. S. ... ... 12 

Plant Legislation in Brit- 
ish Guiana and the 

Caribbean Colonies ... L. D . Clear e . F.Ii. Enl. S. ... ... 25 

SELECTED ARTICLES. 

Presidential Address 
(Fourth International 

Grassland Congress) ... Prof. R. G. Stapledon, C.B.E., J/.A. ... 39 


The Boring Points for 
Refractometer Tests of 

Sugar Cane ... C. Cameron & II. B. Singh ... ... 47 


Coffee Quality 

• It Ml 

... 

51 

Bronze-Leaf Wilt Disease 
of the Coconut Palm ... 

NOTES. 

t • • • * « 

** 

54 

Rotenone Yielding Plants 
of South America 

• ■ • • • • 

» » * 

57 

Surinam and Curacao 

i 

<n « * # 

i * • 

58 

Soil EroBion 

» • « • • • 

... 

59 

Clarification of Sugar 
Syrups 

» • « * • • 

... 

... * (51 

Legislation ... ... 

• 

It* 9t« 

Ml 

62 



Contents— Continued . 


REVIEW. 

Page 


The Practical Aspects of Copra Deterioration ... ... ... 63 

MEETING OF B.G. BEEKEEPERS’ ASSOCIATION ... ... 04 

NEWS ... ... ... ... ’ ... 67 

PLANT AND SEED IMPORTATION ... ... ... 69 

METEOROLOGICAL DATA ... ... ... ... 70 

CURRENT PRICES OF COLONIAL PRODUCE ... ... 7a 


ILLUSTRATIONS 




Facing 

Page 

Plate 

I.— Fig. 

1 — Grasses and Young Courida at Nog Kens 

4 

.. 

Fig. 

2 — Spartina Grass Growing at Kitty foreshore 

4 

Plate 

II.— Fig. 

% 

3 — Various Grasses and Plants growing on 

Foreshore. Hope, East Coast, Demerara ... 

5 

»» 

•» I ig. 

1 — Mangrove Trees on Essequibo ("oast 

5 

Plate 

III.— Fig. 

o — Courida trees being rapidly eroded by wave 
action at Union, West Coast, Demerara 

6 


» I ig* 

fi — Holes formed in the Foreshore by tallen 
Courida trees and stumps 

6 

Plate 

IV.— Fig. 

7 — Young Mangnrse trees planted behind 
a bamboo pallisade 

7 


Fig. 

8 — Young Mangrove trees planted in front 
of earth dam 

7 

Plate 

V.— Fig. 

0 — Sand spit formed at Hidden Fleece, Jan- 
uary, 11*33 

8 


,. — Fig. 

10 — Landward view from Golden Fleece 
groyne in January, 1035 

8 

Plate 

VI.— Fig. 

11 — Landward yiew from Golden Fleece 
gro\nein September, 1035 

9 


„ — Fig. 

12 -^Natural Sand, and Shell embankment at 
Woodlands, East Coast, Demerara 

9 

Plate 

VII.— Fig. 

13— -Natural Sand embankment at Suddie 

Esfeequibo 

10 



The 

Agricultural Journal of British Guiana. 

March, 1938. 

EDITORIAL 


GRASSES. 

Animals depend for a living on the vegetable kingdom, and rely more on 
one family in this kingdom than on all of the three hundred other families of 
flowering plants combined. The family of such outstanding importance is the 
grasses, and there are some who contend that as the path of civilization pro- 
gressed its course was directed in no unmistakable manner by the nature of the 
grass which grew in a particular region. The distinctive Malay and Chinese 
civilization was based on rice, the Ar>an and Semitic civilization was bused on 
wheat and barley, primitive African civilizations were based on the sorghums ; 
in America there was yet another type of civilization based on maize — a grass 
entirely unknown in its wild stage so long has it been cultivated. 

In -the grasses are included the cereals — wheat, barley, rye, oats, millet and 
sorghum of the Old World, rice and maize of the East and of tho New World. 
The culture of cereals dates from time immemorial. Records show that even 
in the twelfth century production of these crops was already intimately woven 
into social customs and habits ; it appears, for instance, that wheat bread was 
associated with the luxury and entertainment of the upper classes. A Latin 
poem, published about that time, draws attention to a custom which found 
favour with the housewife of those da> s and which doubtless was tho forerunner 
of some of our modern university courses in Home Economics : — 

“ With common pit we they buy, 7 is said , 

“ .4 single loaf of whenten bread . 

“ They /ml if under loth and hey , 

“ And if a guest they chance to sec, 

"/They bid the servant go for if — 

“ But no one dares to cut a bit / 

Rice, it may be mentioned, is considered the world’s greatest crop and forms 
the staple diet of more people than any other food. * 

In this family too, are the pasture grasses of the world. Primitive man 
depended largely on the animals he could kill and was, therefore, vitally associated 



‘ AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


lit., i. 


2 

with grasslands for good grazing fields and food. The position has not changed 
greatly in the twentieth century. Elsewhere in this Journal is reprinted the 
Presidential Address to the Fourth International Grassland Congress which was 
held in Aberystwyth last June. A new orientation which in recent years has 
come more and more into prominence is that pasture grasses, being of such far 
reaching importance, should receive care and attention equal to that given to 
crops. Agricultural communities can no longer afford to permit their pastures 
to be untended and indiscriminately grazed. In the words with which Professor 
Stapledon closes his address : “ If the people of the world, and to a man, are 

indeed to be adequately fed with fresh food of the highest quality, and balanced 
in every respect, then the enormous acreage of the world that stands in grass- 
land of every character, and of no character at all, must be brought to play 
its full part.” 

In this same family are to be found the sugar cano, the oil grasses, the 
bamboos. 

The grasses as a family an*, therefore, of extraordinary importance to the 
world in general and in the case of mmy a tropical country their importance is 
strikingly emphasised. In British Guiana, for instance, only a relatively narrow 
coastal strip has been colonized and agriculturally settled; it is mainly on the 
output of this narrow strip that the economic life of the Colony is based. Thus 
far there are only two important crops that have been successfully exploited on 
the typical coastal soils, and both of them — cane and rice — are grasses. Latest 
available figures show that cane products are responsible for 68% of the Colony’s 
exports and rice for 7% ; not only are these crops ot importance to the Colony's 
well-being but with the present outlook they are an essential for its very 
economic existence. 

In the account with grasses, the entries are not only on the credit side. 
There is no winter in tropical countries to serve as a “ closed season ” and to 
interrupt the growth and spread of weeds ; in consequence weed control has 
become one of the most important, one of the most expensive of tropical 
agricultural operations. The difficulties which are presented in effectively con- 
trolling weeds are responsible to a larger extent than is usually appreciated for 
the lack of good husbandry to which attention is so frequently drawn in the 
case of small-farming in the Tropics. Farmers in this country, as in many others 
have fallen into the habit of interchanging the word “ grass” for ” weeds” quite 
indiscriminately, for the simple reason that most of the weeds of consequence 
are grasses. 

Although in British Guiana the fodder and pasture grasses are not playing 
the part which it is envisaged that they will one day play when by intelligent and 
orderly management a more thriving livestock industry will be supported, the 
Livestock Division of the Department is endeavouring to make pasture improve- 
ment one of tUj| important features of its work. A visit to the stock farm 
paddock at Georffebown will show what can and ought to be done. 



BMfOBUL 


3 


A direction in which the grass family is of peculiar interest to British 
Qniana is in regard to foreshore reclamation and conservation. In an article 
elsewhere in this Journal, the Director of Public Works and Sea Defences points 
out that the presence of vegetation on the foreshore of British Quiana plays an 
important part in reducing erosion. One of the plants found valuable in this con- 
nection is a grass, Spartina , which is giving- useful service in foreshore 
conservation in this country. 

In the subject matter of this Number reference to the grass family is made 
in more than one of the articles. For so important a subject such prominence is 
deserved. 



ORIGINAL ARTICLES. 


THE USE OF VEGETATION FOR COAST PROTECTION. 

BY 

GERALD 0. CASE 

Director of Public Works and Sea Defences. 

“ When 1 have seen the hungry ocean gain 
“ Advantage on the kingdom of the shore 
“ And the firm soil win of the watery main 
“ Increasing store with loss and lass with store; 

“ When I have seen such interchange of state, 

“ Or state itself confounded to decay ; 

“ Ruin hath taught me thus to ruminate." 

Shakespeare, Sonnet LXIV. 

Formation op British Guiana CoastiAnds. 

The general evidence seems to prove that the present cycle of coast-line 
changes in British Guiana was started by an alteration in the relative levels of 
land and sea, which cause the formation of a very wide foreshore at low tide. 

Every foreshore has a natural inclination of repose and at the commence* 
ment of the present cycle of coast-line changes in this country the gradient of 
the foreshore was flatter than the natural inclination. In consequence of this 
a natural embankment of sand and shell was built up where the waves broke at 
high tide. There were numbers of gaps in the naturally formed embankments 
through which the rivers discharged into the sea. Behind the naturally formed 
embankments was a large area flooded by the sea at every high tide. 

The flood tidal current brought in silt and the rivers brought down sand 
which was deposited at slack water causing salt marshes to be gradually formed 
behind the natural embankments. 

In the formation of these salt marshes vegetation played a very important 
part in organising and controlling the accretion. Plants which grow on 
sheltered areas covered at high tide and dry at low tide slow down currents and 
cause material to be deposited Which in the absence of vegetation would be 
held iu suspension and moved nmy. Numerous marine animals dwelt among 
the plantB and their remains Wd the decay of the plants themselves caused the 
formation of the fertile sughr estate lauds in British Guiana. 

At the time of the first occupation by Europeans of this country, it is 
highly probable that the rate of erosion due to the gradual inland movement of 
saud and shelV^embankments was very small and perhaps negligible as they 



Plate I. 



i «r ] (viissis nid v»ung ( ouj id i it N ng Etn^ E i^t Poi^t, Dcniti ua, taken o\ ci b> sei 

owing to » bituli m ^ i w ill 



Fij? 2 Spattnui (tiiss giowmg it Kittj Foieslioie Fist (oisi, Dtuiei iru 



Plate II. 



Fig. 4. — -Mangrove trees on Essecjuibo Coast. 




5 


TO! toM 09 dOASf PROTWraJT. 

were probably eowred ’with vegetati on* Reclamation of the land behind the 
And and shell embankments was gradually dehiered by building dams at right 
a&gta* lie the coast-line and putting kokers oil the site of the smaller streams 
passing through the embankments or by cutting through the embankments and 
building kokers in line with them. It is highly probable that very soon after 
the commencement of the reclamation works sea defence troubles commenced as 
all naturally formed sand or shell embankments travelled inland unless fixed by 
vegetation. History shows that in many countries man did not at first 
appreciate the value of vegetation in fixing naturally formed sand embankments 
and preventing them gradually moving inland. In consequence the vegetation 
was often destroyed, and as the embankments gradually moved inland the 
kokers became exposed to the violent wave action as also did the artificial 
man-made embankments built to fill in gaps between the natural embankments. 
Erosion and gradual disappearance of the naturally formed sand and shell em- 
bankments was largely due to artificial causes arising from the empowering of 
the marsh land and interference with natural drainage conditions. 

On the parts of the coast-line of British Guiana where lands have not been 
empoldered, especially between the Pomeroou and Waini rivers, there still exist 
long lengths of sand and Bhell embankments clothed by vegetation and here 
there are no sea defence problems, but on the East and West Coasts there are 
only comparatively few of the natural embankments left. 

On the Essequibo coast a natural sand embankment still protects low-lying 
land north ot Suddie from inundation by the sea. Such sand embankments are 
found on the West Coast of Berbice and on the Corentyno Coast. 

It is important to place on record the useful part which vegetation can play 
in preventing erosion of naturally formed sand and shell embankments so that 
in the future reclamation of any area behind naturally formed embankments, 
such as the large area between the Pomeroon and Waini rivers, care may be 
taken to preserve existing vegetation and plant more where necessary. 

ZONEH OP V BkSliTATION. 

The vegetation of the sea-bed, foreshore and on salt marshes may be 
divided into zones : — 

1. Sea-bed. 

2. Foreshore covered by the sea at neap tides (area between high- 
water line of neap tides and low-water line of neap tides). 

3. Foreshore covered by the sea at spring-tides only (area between 
* high-water line of neap tides and high-water line of spring 

tides). 

4. Salt marshes covered only by the occasional highest spring 
tides. 

5. Sand embankments above high-water level of ordinary spring 

tides, 



6 


AGSKStrttWlUt JMBMU9MM 1 1MMII OWMi 


‘jft rfc i 


Included fa these none* we find various species of . both hydrtiphyt** ana 
hallopbytes, -which grow on sand and mud, and -which aoetunulate and fit 
material transported by the tides and currente. The decay of these plants isiso 
adds to the rising surface. The plants are usually distributed in zones, and 
often very gradually pass over into salt-marsh formations. In shallow beds of 
seas associations of microphytes and the large algae grow on sand and mud. 
The hallophitic communities are divided into those that are psammapbilons, 
pelophilous and helophilous, according as the substratum consists respectively of 
sand, of mud or of swamp. 

Whenever there is a breach in the line of sea defences and the sea dam Is 
retired forming a bay to the general line of defence the salt water first kills out 
the land grasses and plants and then oourida trees start to grow. 

Fig. 1 shews young courida and salt grasses now growing in the bay caused 
by retiring the sea dam at Nog Eens owing to the big breach in the sea wall. 
The vegetation slows down the tidal current and accretion takes place at a 
more rapid rate than it would do in a bay without vegetation. The tendency 
is for erosion to take place at headlands and accretion in bays. 

Beyond low-water line in Europe and parts of Americb, “eel” grass or sea 
grass ( Zostera marina ) often grows on the sea bed and rapidly accumulates sand 
and mud, but it is tfot found in British Gniana. When the shore has been raised 
to above low-water mark of ordinary spring tides, Spartina grass, Batis and other 
plants commence to grow, and when they in their turn have raised the level 
to above high-water mark of neap tides, other plants assist in the work of 
reclamation up to high-water level of ordinary spring tides. 

I do not propose to give any detailed description of the foreshore vegeta- 
tion in British Gniana, and would refer interested readers to the article by E. B. 
Martyn, published in the Journal of Ecology, Volume XXII, No 1, 1934, 
describing the foreshore vegetation eastward of the Kitty groyne. 

On the coasts where the shore is of a rocky nature and high tides wash the 
base of the cliffs, and also where there is a comparatively smal) horizontal range of 
tide, marine vegetation and animal life produce little effect in causing accumu- 
lation. Three conditions are necessary for the formation of salt marshes on 
tidal foreshores. Firstly, the foreshore must be sheltered from rough seas ; 
secondly, there mast be an ample supply of sand and mud brought in by the 
tides or carried down by the rivers ; and thirdly, there must be an adequate 
number of suitable plants growing on the foreshore. 

The algae which grow on the sea-bed are usually attached to stones or 
rocks, mid are not of much importance in raising the shore level. There are, 
however, a few species having capillary root-like organs which grow in masses 
on loose sand or mud. These grow on sandy shores in sheltered bays and 
estuaries, where there is a tendency for accumulation to take place. They assist 
the process of accretion in several ways. Firstly, the algal growth slows down 



Flats III. 



Fig. C.— Holes formed in the foreshore by fallen courida trees and stumps. 


PLATB IV. 




m mm m vwwAfio* ton coast protection. 7 

the currents and causes sand and mad to be deposited and collected ; secondly, 
the carpet-like covering of seaweed forms a protection to the shore end tends to 
prevent erosion daring gales ; thirdly, the decay of the embedded Beaweed in the 
gradually rising shore surfaoe forms a humus, the sand being thus manured, and 
a soil is formed in course of time in which the higher forms of vegetation can 
grow. 

On tidal mnddy foreshores in many places various species of flowering 
plants (chiefly grasses) grow strongly from high-water to half-tide level, and 
form a dense mass (Pigs. 2 and H). As the surface is gradually raised by sediment 
deposited by the incoming tide, and in some cases by streams bringing debris worn 
from the land, and by accumulation of dead vegetation and shell-bearing animals, 
a salt marsh is formed and gradually grows seaward. The ordinary species of plants 
which build up salt marshes do not do so above ordinary high spring-tide level 
as they require to be covered periodically by the sea in order to flourish. When 
salt marshes have grown upwards to about ordinary high water level, the accu- 
mulation of material subsequently takes place at a very slow rate, as the condi- 
tions are then unsuitable both for salt marsh and land plants. BusheB, trees 
and the higher species of vegetation will not, as a rule, grow on marshes covered 
at occasional high tides, even by a few inches of sea-water, although there are 
important exceptions. 

In British Guiana Spartina grasses and Batis are perhaps the most important 
plants on the first zone landward of low-water level. Near low-water mark 
black masses of sand are often inhabited by iron-snlphnr bacteria, the black 
colour of the sand being due to the reduction of sulphates dissolved in water 
contained in ferruginous sand. On muddy foreshores of estuaries and bays, there 
are sometimes shallows which contain water even at low tide. In such places 
several Bpecies of tall, perennial plants grow in dense masses, and accumulation 
on the bottom gradually takes place. 

Spartina grasses are the most valuable grasses growing on the foreshore 
between high water of ordinary neap and spring tides. In sheltered bays and 
estuaries these grasses are very effective, in causing the reclamation of tidal 
muddy foreshores. Altogether there are about 1 8 known species* of Spartina, 
mostly natives of America. With a few exceptions they grow on Salt mashes 
and muddy foreshores which are covered by spring tides. In places these 
grasses rapidly overrun large areas, hundreds or even thousands of acres 
of foreshore ; their extensive roots fix the shore material and prevent it 
from being washed away. The mass of leaves to some extent breaks 

*With reference to species of Spirtiim grass referred to, it may be noted that the 
Department of Agriculture carried out trials on the foreshore some years ago with S. Town- 
wrtihi, a species winch hits proved of enormous value as a foreshore colonist on the coasts of 
England, France and Holland, and which was recommended for trial in other parts of the 
world. i Though it grew well in the Colony when established, it was however unable to com- 
pete with the indigenous speciess S. bratiliemU, which completely smothered it when the two 
came into contact. References to the two trials may be found in the Govt. Botanist's report 
for the years 1931*83 inclusive, and a summary of trials with these two apecies, made here and 
w other mpat countries, was published in the Kev Bulletin of Mite. Information, 1936, p, ‘21, 



8 


AORIOT&TTTBAL JOTJEKAL OF BRITISH OSTIA**, 


[IM* 


the force of the waves, slows down the current, and causes accumulation 
of material on the shore which is thus gradually raised. The decay of the 
leaves and roots forms a humus, and therefore, while the shore level is 
being slowly raised, a soil is being formed which, when the level is raised high 
enough, will be eminently suitable for the other kinds of plants. Numerous 
shell-fish and animals dwell among the grasses, and their remains help to raise 
the shore level. 

In Dr. Stapf’s opinion Rice Grass mainly spreads by seed. The grains fall 
with the spikelets, which float, and are transported by the tides and currents to 
neighbouring shores, where they germinate. He suggests that the seeds may 
possibly lie in the water over the winter and germinate in the following spring. 
The seedlings soon grow into tufts, with plenty of stolens radiating in all 
directions, and anchor themselves to the shore by long thread-like roots which 
descend vertically. There is no difficulty in transplanting Spartinas. 

Most grasses and plants which grow in salt water die as soon as the accumu- 
lation has been raised to high-water level ; an occasional covering of salt water 
being necessary for their existence. Tidal forest trees, however, in sheltered 
places grow and accumulate detritus from below low- water to above high-water 
mark, thus completing the reclamation of the foreshore and sea- bed without 
artificial aid. 

On sheltered parts of the sea-coast and in estuaries and lagoons, in or near 
the Tropics, certain species of trees are \ery effective in causing accumulation 
from below low-tide to about high-tide level. Unlike most vegetation, the tidal 
forest trees will in sheltered places grow in moderately deep water. 

The tidal trees which fringe the coast line on sheltered shores in bays and 
estuaries form a dark-green dense belt of low trees, which, in addition to causing 
the reclamation of tidal foreshores, also tend to protect the coast from slight 
erosion. The trees raise the surface of the sea-bed and foreshore in much the 
same way as the lesser forms of vegetable life that is, by slowing down the 
currents and causing the deposit of sand and mud which is carried in suspension 
in the water. The roots of the trees also accumulate a lot of material which 
moves along the bottom by the action of currents and waves. The decay of the 
large number of marine animals which dwell among the foliage and leaves con- 
tributes debris to the rising surface level, and rich black soil is thus formed, 
which between the tide limits is evil -smelling and abounds with bacteria. Several 
species of Crustacea burrow in the subsoil, bury dead leaves, and play a similar 
part to that of earthworms on land. 

Warming, in his work on the Ecology of Plants, states that tweniy^six 
species of plants grow in tidal forests. Tidal forests arc often called “ man- 
grove marshes ” as the mangiwe trees (species of Rhizophora) are the most 
important trees inhabiting tidal waters in the Tropics (Fig. 4). The trees arrange 
themselves zonally to a certain extent, the species of Rhizophora being generally 
found iu the deepest water. The 44 air-roots ” or 44 prop-roots ” are an interesting 



Plate v, 



Fig. <♦. Sand spit formed at Golden Fleece, Kssequibo, in January. Fd.io. Vegetation 
just starting to establish itself. 



Fig. 10. — Landward \ iew from Golden Fleece groyne. Kssequibo, in January. 11)35. 


Plate VI. 



| i^r n — Luuiw ii<1 M(\\ fiom (»oldm I hue h noMu I nsmjuiIh) m Si ptembti lbt,> r l lie 
tisunui tuid dim 1^ pi ntn ilh hidden 



I 12 — \itui d Mild d id shell i mbmkment it Woollmds lust Coist Dtmtriri 


wti vm of vmv ution for coast protection. 


9 


feature of many of the tidal trees. There are either erect or kneed branches of 
the roots which project above the shore surface. They are provided with 
minute openings (stomata or lenticles) which allow air to pass in and be carried 
by means of passages in the soft spongy tissue to the roots embedded under the 
shore. The “ prop-roots ” also serve as supports to the trees and securely fix 
them to the sea-bed. The power of resisting bending caused by wind or sea is 
much greater in the case ot trees having aerial roots than those having a 
main stem only. 

The tidal forests multiply by seeding and also by means of runners. In 
several species of Rhizophora the embryo plant grows into a more or less 
developed plant while still attached to the parent tree. Long radicles emerge 
from the seed and descend rapidly towards the shore surface where the latter 
may establish itself before falling off the parent tree. If the seedlings break 
loose and fall into the water or mud, their club-shaped pointed roots enable 
them to fix themselves into the mud ; or if the water is too deep, the seedlings 
are transplanted by the current, and may strike root on another part of the 
coast. Some of the seeds of the tidal forest trees are provided with devices 
which enable them to float. 

On the E ist Coast, Demerara, courida trees grow freely above mean sea level 
and in the estuaries of the large rivers mangrove is usually very plentiful. 

C nirida is useful in building up and consolidating a muldy shore subject 
only to overflow at high spring tides, but, on the other hand, it is useless to 
prevent violent erosion by wave action. If severe erosion starts the courida 
stumps are very harmful, and increase the rate oi erosion. In the past it has 
been necessary to spend large sums of money in removing courida stumps from 
the East Coast foreshore (Figs. 5 and (»). 

From a health point of view the coast-line of a belt of courida is, in 
populated areas, very objectionable. When an exposed foreshore, subject to 
wave action, has built up to about high tide level, the courida has practically 
completed its work in causing accretion and there is no objection to its removal 
provide l all the stumps are taken away ami the foreshore planted with spartina 
or other suitable grasses which will cover it. In estuaries, where the shore is 
sheltered from violent wave action, inmgrose trees are a \ery effective protec- 
tion against erosion aud should not be cut down. 

On parts of tho Islands of Wakenaam and Leguan the mass of mangrove 
roots effectively protects the coast from erosion by current action. In many 
cases erosion has been started by cutting down the mangrove at the koker 
outlets to provide a landing place for boats. Efforts are now being made to 
re-establish the growth of mangrove in abandoned boat landing places by form- 
ing a pallisade of sticks or bamboo and planting young mangrove trees behind. 
The pallisade is at first necessary to protect the young plants (Figs. 7 and 8). 



10 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[IX, 1. 


In connection with this matter it is important to differentiate between the 
effect of a mass of tree stumps or roots on a shore subject mainly to current 
and a shore subject to heavy wave action. On the protected shore subject 
chiefly to current action tree stumps and roots are effective in slowing down 
the current and preventing erosion. On shores which suddenls y become subject 
to violent wave action the tree stumps and roots cause erosion and aid the 
destructive forces o£ the waves. Holes are formed round each root stump 
lowering the foreshore and causing the uneven surface to be more easily 
attacked by waves. 

Sand embankments and sand spits enclosing bays are sometimes formed where 
there is a predominant littoral drift in one direction. When the sand bar has 
been raised to mean tide level vegetation actively assists in raising the shore 
level landward of the spit or embankment. Figs. 9, 10 and 11 illustrate a sand 
spit formed at Golden Fleece, Essequibo Coast, in 1935 and the action of vegeta- 
tion in building up the shore. 

Sand and Shell embankments. 

In the actual formation of sand embankments abpve high water level 
vegetation plays a very important part. On foreshores where there is sand it 
is dried by wind an*l sun at low tide, and as soon as it becomes dry the wind 
is able to transport it inland. As a general rule, the prevalent winds are onshore, 
and such winds are more effective in moving sand inland than the loss frequent 
seaward winds in moving sand back again. 

Sand embankments on the coast-line above high water level are generally 
formed by the accumulation of sand against some obstruction. Trees, shrubs, 
grasses, fences &c., may occasion the lodgement of sand in considerable quantities. 

On the seacoast, the formation of embankments is chiefly due to vegetable 
life. The various kinds of grasses which grow in sand just landward of high 
water are very effective sand collectors. Each plant or group of plants forms 
in effect an openwork fence and collects sand in the manner previously 
described. Many of the various grasses which thrive on sandy coasts grow 
upward as the sand accumulates ; thus in time dunes of considerable size are 
formed. 

Where there is insufficient vegetation to fix sand embankments properly 
as they are brought into existence on the coast margin, they are rapidly moved 
inland. InEurope large areas of fertile land and even villages have been 
completelJjjBhgwhelmed bv the advancing sand; and sand deserts as a con- 
sequence iOT^Pd. The inland movement of unfixed sand embankments has 
often resulted in the inland movement of high-water line, thus causing serious 
erosion of the coast as well as the devastation of the land. In places where the 
sand blown inland from the foreshore not replaced by sand brought in by sea 
action or littoral drift, the erosion of foreshore naturally takes place, 



1) XiUmlsiml tinWinkineni »t EsMqmbo, o\eu»io\\n with Ipomwa h/loba 





Tint USE OF VEGETATION FOR COAST PBOTlOTIOir. 


11 


The velocity of the inland travel of a sand embankment is the rate of 
advance of the crest, which takes {dace by the accumulation of sand on the 
steep lee slope. The supply is brought in two ways : firstly, by the rolling of 
coarse sand grains over the crest ; and secondly, by the deposit of part of the 
the vegetation flying sand caught by the eddy and not tossed away again. 

If covered with vegetation sand dunes form a consolidated barrier against 
the encroachment of the sea. The roots of the various grasses and plants bind 
the surface, and the foliage catches and retains sand abstracted from the fore- 
shore by wind action (Figs. 12 and 13). The dune thus grows in height and width, 
the vegetation in many cases accommodating itself to a rising surface level. 

On the Gascony coast of France, coast sand dunes were formerly moved 
inland by wind action, causing erosion of the coast and devastation of the land 
by the formation of a miniature Sahara. All this, however, hffg been changed 
by the work undertaken by the French Government, and insteg# Af vast areas 
of bare desolate sand, there are now productive pine forests. The success of 
this work was largely duo to the initiative of a French engineer, M Bremontier, 
who, over a hundred years ago, devised a system for fixing and reclaiming the 
Gascony sand dunes. 

Documentary evidence shews that at the time of the first Roman reclama- 
tion of Holland the sand embankments were clothed with trees on their land- 
ward slopes and in places even partially down the seaward slope. Old 
geographers describe forests on the dunes extending to very near the sea. There 
is little doubt that not realising the value of the trees for fixing the dunes and 
preventing their inland movement, the trees were cut down with the result 
that in the Middle Ages chroniclers refer to the drifting sand embankments. 

The growth of grasses and small shrubs on the sea face of the dunes down 
to high water level of spring tides, is essential to bind the sand and collect fresh 
inblown sand. 

In the past the vegetation wa9 often damaged by pedestrians and cattle. 
Now very stringent laws are enforced in Holland to ensure the careful preserva- 
tion of vegetation and the coast is constantly patrolled. 

The efficiency of vegetation in consolidating sand dunes and preventing 
coast erosion has for many years boen widely recognised, and numerous lawg have 
been passed to prevent its destruction. 

In the reign of Queen Elizabeth an Act was passed to prohibit the des- 
truction and to encourage the cultivation of vegetation on sand embankments. 

In early times there were laws in force in numerous manors in England to 
prevent injury to coast sand embankments. The Records of the Manor of 
Ingoldmells in the County of Lincoln, shew that in the reign of Edward II, five 
Orders of Attachment were made against various persons for “ doing damage in 
pasturing on the sea banks, for mowing the dunes and herbage outside the 
bank of the sea, against the defence of the sea for the salvation* of the 
country, at the Manor Ingoldmells ” 



STATUS OF THE AMAZON FLY IN BRITISH GUIANA, 1937. 

BY 

L. D. CLEARE, F.R. ENT. B., 

Entomologist, 

Vrjiartmcnt of Agriculture, British Guiana. 


Introduction. 

It ia necesaary to follow for a number of year8 the 8tatua of an introduced 
parasite in its new environment before an opinion can be formed as to the role 
the insect is playing in combating the pest for which it was secured. 

Examinations made on sugar estates at different times after the introduction 

of the Amazon Fly into this country showed long since that the insect had 

established itself not only in sugar-cane but also in rice, and as regards the 

former crop at least was parasitizing a fair proportion 'of the Diatrara 

sacchuraUs in that host plant. 

% 

A survey carried out about the middle of 1935 by Mr. F. A. Squire, while 
engaged as Supernumerary Entomologist in this Department, showed further 
that some two years after the introduction of the parasite and the colonization 
of the sugar estates the insect was still doing good work. The results of this 
survey were not published. 

About a year ago it was considered desirable to undertake another survey, 
and in January 1937, the work was commenced, continuing, as opportunity 
allowed, to January 1938. In the present survey it was not possible 
to carry out examinations of all + be sugar estates in the Colony owing to the 
pressure of other work and the limited staff of assistants, but a total of fifteen 
sugar estates was examined during the survey extending from Pin. Skeldon 
on the extreme east of the Colony to Pins. Versailles and Schoon Ord on the 
West Bank of the Demerara River. It is believed, however, that both the 
number of estates examined as well as the area o\er which they are extended 
are sufficient to allow the results to be considered as being representative of the 
general conditions over the sugar-growing area. 

As regards Pin. Albion, llerbice, the survey of that estate was carried out 
in conjunction with Mr. H. W. B. Moore, Entomologist of the estate, who 
undertook the field collections of material. 

Colonization of the Sugar Estates, 1933-35. 

Before dealing with the present position of the fly, some information As 
to the introduction of the insect and the subsequent colonization of the estates 
will be given. , 



Status Of tab amajson ?ly in British Guiana, 1937. 


13 


The first consignment of the Amazon Fly arrived in British Guiana from 
Brazil on 30th August, 1933, and between that date and 31st October, 1933, a 
total of six consignments was received totalling 3,000 puparia, and from these 
1,409 flies were secured. From these initial stocks some liberations were 
made directly into the sugar-cane fields, as well as material obtained to start 
extensive rearing operations. 

Rearing of the fly was commenced at Headquarters Laboratory on the 
Sugar Experiment Station as early as 21st September, 1933. Later as the work 
progressed laboratory assistants were trained in the technique of rearing the 
insect and field laboratories sot up in conjunction with the different estate 
authorities on ten sugar estates scattered over the sugar area of the coastlands. 

These estate laboratories served to stock the plantations on which they were 
situated, and which in most instances were at too far distances from Head- 
quarters to be stocked from there. Such estate laboratories were situated in 
the county of Berbice and on the East Bank, West Bank and West Coast, 
Deinerara. All the estates on the East Coast, Demerara, besides a few on the 
East and West Bank Demerara and in Berbice, were colonized solely with flies 
reared at the Headquarters Laboratory. 

During the period these laboratories were in operation a total of over 
379,000 flies was reared in all laboratories, of which over 18,000 were produced 
at Headquarters Laboratory. As regards Headquarters Laboratory, work ceased 
in April 1935, and no flic3 were supplied to the estates which were colonized 
from this laboratory after that date. Many of the estate laboratories continued 
rearing for a few months longer, however, but by September or October 1935 
practically all had ceased work in this direction. There were a few exceptions 
to this where the rearing of flies continued for some time longer, namely, Pins. 
Port Mourant and Leonora to November 1935, Pin. Albion to December 1935 
and Pin. Blairmont to June 1936. 

Table I gives the number of flies distributed to the estates from Head- 
quarters Laboratory, between September 1933 and April* 1935, and Table II 
shows the number of flies reared in all laboratories, between September 
1933 and November 1935. 

For about three years, therefore, as far as the East Coast Demerara estates 
are concerned, and from about the end of 1935 in most other instances, the fly 
has been continuing on its own, under conditions that it must meet and survive 
if it is to exert any control on Diatraea m the Colony. Just how well it has 
accomplished this the present survey will show, in part at least. 

Method of Survey. 

In explaining the method used in obtaining data in the present survey 
some acconnc of the habits of the moth-borer and of the fly will help. In the 
early stages of the attacks of moth-borer on sugar-cane the larv® bore into the 



Tables I. — Amazor Flies distributed from Headquarters Laboratory to Sugar Estates for Colonisation 

or as Breeding Stock, 1933-35. 



Principally Breeding Stock. 



NO. OF FLIE»n 


&¥ATU 8 OP THE AMAZON tit lit BRITISH GUIANA, 1931 15 


TOTALS 

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16 , AGRICULTURAL JOURNAL OF BRITISH GUIANA. £ IX, 1. 

young stalks and destroy the central leaf, producing what is generally termed a 
“deadheart.” When the stalk has reaohed the stage of jointing, however, it is 
not normally killed, the moth-borer larva: boring into such stalks and tunnelling 
them to a greater or less extent. 

The Amazon Fly in attacking the moth-borer larva: deposits eggs or larva: 
at the entrance of the moth-borer tunnels or in their vicinity. The larva: so 
deposited, directed either by smell or reacting to some other stimulus, enter the 
borer tunnels and eventually lind their way to the Dial rani larvae. Having 
entered the Dial rant larva: the parasites continue to develop, and by the time 
they are ready to pupate the host larva has succumbed so that the parasite is 
able to leave the then mere remains of the moth-borer larva. The parasite then 
pupates, either about the entrance of the moth-borer tunnel, or sometimes out- 
side behind a leafshoaf, or even, occasionally, at the base of the plant on the 
ground. 

To obtain an estimate of the work of the parasite in the field it is necessary 
to ascertain the number of the host parasitized, including such of tho parasites 
as are found in the pupal stage at the time of the examination. 

For this purpose field examinations were made, and data compiled there- 
from. In these examinations fields of between six weeks and two months old 
were used, as it was considered that this would be representative of fields which 
would be normally worked were “ borer gangs ” being employed in hand 
collecting, and would contain a fairly representative Diatuini population 
in their young stages. 

In each such field the collection of Diatram was undertaken on a fixed 
method, which consisted of making collections in the field at 10 places spaced 
about equally across the field diagonally. At each of these places the “ dead- 
hearts ” in two rows were cut and examined. In each field it was the en- 
deavour to obtain at least 100 Dialrara larva 1 in the collection, but if the 
Diatraea population was low (as often occurred) this was not always possible 
and under such circumstances the examination of the field continued, 
cutting “ deadhearte ” from rows in the same areas, for z period of 3 boy-hours. 

The Diat ram larvae were collected from these “deadhearts”— both D. soc- 
charalis and D. canHla were secured, as were also the living Diatraea pupae and 
Amazon Fly puparia ; the result wa3 noted on a form, and the material brought 
back to the labatory for examination. 

Diatraea larva: obtained in the field examinations were subsequently dis* 
sected in the laboratory and the actual parasitism noted, while the Amazon Fly 
puparia collected were kept for emergence of flies and hyperparasites. 

On each estate at least twelve fields were examined (Pin. Farm excepted 
where only seven fields were examined) for preference on consecutive days, but 
in two instances suoh examinations comprised a larger number of fields and/or 



STATUS OP THE AMAZON PLY IN BRITISH GUIANA, 1037. 


17 


were taken at two different periods. There was no selection of fields beyond the 
limitation of age, which has already been mentioned, and an attempt to have the 
number of fields examined distributed as nearly as possible equally among the 
stands, namely, plants, first, second and third ratoons. Usually the fields on the 
estates which complied with the conditions as regards age were listed by the estate 
authorities at the beginning of the examination of each estate, and from such lists 
twelve were selected at random so as to be distributed over the cultivation. 

Results of the Survey. 

Fifteen estates in all were taken in the survey and on these a total of 212 
fields were examined, comprising 88 plant fields, 54 first ratoons, 56 second 
ratoons and 14 third ratoons. Of the total of 212 fields, in 155 fields (73.1 per 
cent.) the Amazon Fly was found parasitizing either 1). saccharalis or D. canella 
or both, 144 fields showing a parasitism of 1). saccharalis only, but no field was 
found in which only I). canella was parasitized. 

In these fields a total of 37,332 “ deadhearts ” were cut out, of which 20,998 
or 56,3 per cent, were empty. Of the remainder, 14,274 (37.9 per cent, of the 
total) contained living Diutraea, in the proportion of 6,271 or 43.9 percent, 
D. saccharalis (the black-headed borer) and <8,003 or 56.1 per cent. 1). canella 
(the yellow-headed borer), 2,060 or 5.5 per cent, of the “ deadhearts ” were the 
result of “ Other Causes ” including white grubs (hard back beetles) and rats. 

Table III gives the details of these figures as regards each estate. 

In 5,371 D. saccharalis found in Positive Fields, 863 or 16,0 per cent, were 
found to be parasitized by the Amazon Fly at the time of examinations of the 
fields (“ Current Parasitism of Positive Fields ”) the parasitism ranging from 
'3.4 per cent, to 36,2 per cent. While of the total of 212 fields, 39 or 18.4 per 
cent, showed parasitisms of 1), saccharalis of 30 per cent, and over. If, however, 
all the fields examined are included, both positive and negative 0* Current 
Parasitism in All Fields ”) the parasitism works out at 13,cper cent. L>. saccharalis. 
see Table III. 

The parasitism for D , canella , as expected, was low, 0.32 per cent, for 
“ Positive Fields” and 0.23 per cent, for “ All Fields.” 

As regards the individual estates little need be said. It will be seen that the 
results of the Burveys of Pin. Port Mourant and Pin. Blairmont have been given 
in two sections'each, and some explanation in this respect may be of value. 

On the occasion of the first survey at Pin. Port Mourant the parasitism was 
particularly low, and much lower than examinations on previous occasions had 
revealed. As that examination was made during a dry period it was 
thought that the low parasitism might be attributed to weather conditions. 



Tabu III.— AMAZON FLY SURVEY, 1937-38— RESULTS OF EXAMINATIONS OF SUGAR ESTATES. 








































20 , AGRICULTURAL JOURNAL Of BRITISH GUIANA. [IX, 1. 

Accordingly it was arranged that at a later date when wetter conditions 
occurred, another examination of the estate would be undertaken. The 
second examination, made under similar conditions in all respects except 
as regards weather conditions, gave a much higher parasitism, and it is believed 
that this higher figure was due primarily to this cause. 

The position at Fin. Blairmont was somewhat different. On that estate the 
first examination, which was made under wet conditions, showed a high parasi- 
tism, but owing to the pressure of other work, had to be discontinued after only 
four fields were examined. In January 1938, Mr. G.M. Eccles, Manager of Blair- 
mont Estate, reported a severeiattack of Diatraea in certain fields and opportunity 
was taken to examine these fields to ascertain the position with regard to the 
parasite, and at the same time other fields on the estate were examined to complete 
total of twelve fields and the survey of the estate. 

As to the conditions connected with this outbreak, it would appear that to 
some extent at least the attack was associated with a heavy growth of the grass 
Echinochloa crusgalh cruspavoris (HBK) Hitch. v.hieh occurred after the fields 
were taken in from water-fallow and in which Diatraea mccharalis was present. 
In addition, the four fields attacked are situated at the moBt distant part of the 
estate, and unlike other fields, have no immediately adjacent fields ; there would 
be little possiblity, therefore, of flies spreading into these fields from outside, and 
the population introduced in the normal way with the tops may not have been 
sufficient to deal with the position, or found conditions unfavourable. 

Number of Parasites Per Host. 

Records were kept during the survey as to the number of parasites per host. 
Of a total of 803 Diatraea saccharalt * records, it was found that 313 or 39.1 per 
cent, contained only a single parasite, 203 (30.3 per cent.) contained two 
parasites, 06 (7,0 percent-) contained three parasites, 17 (1.9 percent.) four 
parasites and onlj 4. (0.3 per cent.) contained five parasites per host. 

The pnparia of the fly found in the field agreed very closely with these 
figures and were in the proportions of 59.4, 31.4, 7.5, 1.4 and 0.3 per cent, for 
one, two, three, four, and five parasites per host respectively. 

Hypbrparabitism. 

In January 1937, Mr. H. W. B. Moore recorded a hyperparasite of the 
Amazon Fly from Pin. Albion, Berbice. 

This appearance of a hyperparasite was not unexpected for it had long been 
known that the native fly parasite of Diatraea , Leskwpaipus (Slomatodexia) 
diadema Wied. was attacked by the hyperparasite Signiphora diplerophaga Girault, 



STATUS OF THE AMAZON FLY IN BRITISH GUIANA, 1937. 


21 


and the possibility of this insect attacking Metagoniatylnm was well 
recognised at the time of the introduction of the Amazon Fly. ThiB was con- 
firmed when a determination of the insect was made by Dr. C, Ferricre of the 
Imperial Institute of Entomology. 

In addition. Squire, in his report of 1935, had mentioned the finding of a 
puparium of Metagon i sty turn which apparently had been attacked by a hyper- 
parasite although he did not obtain any specimens of the insect. 

Accordingly during the survey precautions were taken to secure hyperpara- 
sites in order to obtain data as to the prevalence of the insect. 


On four estates of the fifteen the hyperparasite was obtained, namely. Pins. 
Port Monrant, Albion, Diamond and Farm. This would indicate that the hyper- 
parasite is well distributed over the sugar area. 


Of the 45 fields examined on these estates in 13, or 29 per cent., hyperparasites 
were found, while of 1 78 puparia collected, 17, or 9.0 per cent, produced hyperpar- 
asites. If, however, the whole Amazon Fly population of these fields is consider- 
ed, namely 51 0 larvro and puparia, the percentage destroyed by hyperparasites 
would only be 3.3 per cent. 

Table IV gives the details as regards examinations of the ostates in relation 
to the hyperparasitism. 


Table IV.— Amazon Fly Survey, 1937-38. Hyperparasitism of Amazon Fly 
Puparia by Siguiphora dipterophaga. 


| No. of Fields. 

Estate. 


Examined JlXT 


Port 


Mourant 

12 

Albion 

12 

Diamond 

12 

Farm 

7 

Totals 

43 


Puparia. 

Amazon Fly 



Population 
Lame and 

Total. 

With 

Hypers. 

Pupte. 

GO 

5 

1C>3 

38 

3 

148 

37 

5 

00 

43 

4 

115 

, 

1 78 

17 

510 1 


Hyperparasitism 
Per cent. 




Amazon 

Fields. 

i 

Puparia. 

Popula- 

tion. 

•* 



250 

8.4 

31 

20.0 

7.9 

20 

333 

13 5 

5.6 

43.0 

93 

3,5 

27.1 

1 9.G 

3,3 


Other Parasites. 

Other larval parasites, Bmconids, were met with during the survey and note 
was taken of these also. In the saccharalis population in all fields numbering, 
as we have seen, 0,271, Bruconid parasites to a total of 59 or 0.94 per cent.^ were 
obtained, while for a cnnella population of 8,003, 24 Braconid parasites or 0.3 


per cent, were present. 



28 AammmM JomxiAi of samss wiawa [IX t* 

With regard to the native fly parasite Lesktopalpus, unfortunately ho dell 
available. While it is definitely known from observations and examinations 
undertaken daring the period covered by the survey that Leskiopalpus dots 
occur in both the East Coast and East Bank districts, none of the insects was 
obtained in the examinations which actually constituted the snrvey. Accordingly 
no figures are given for the present prevalence of the insect. 

Conclusions. 

From the results given above we may draw some conclusions as to the 
present status of the Amazon Fly in the Colony. 

As the result of this survey it has been found that not only is the 
Amazon Fly present in the fields bnt that it occurred in 73 per cent, of the fields 
examined. That in such fi elds the fly was parasitizing an average of 16.0 per cent, 
of the D. well iralis population and 0.32 per cent, of the D. canella population, and 
taken over all fields these figures were 13.7 per cent, and 0.23 per cent, respective- 
lv. The parasitism ranged from 3 4- per cent, to 36.2 per cent, for Positive 
Fields” and 2 0 per cent, to 33.6 per cent, in “ All Fields.” In 18.4 per cent, 
of “ Positive Fields ” the parasitism of D. sarrharalis was 30 per cent, and over. 

Commenting on the larval parasitism, Myers (1 ) in his very thorough review 
of the Diatrata' situation in 1031, stated that the combined parasitism of the 
eight important parasites was 6 9 per cent, of the borers in cane. The larval 
parasitism by the Amazon Fly of 16.0 per cent. D. saccharalts in the present 
survey must, therefore, be considered as very satisfactory. 

As regards the other larval parasites, the Bracomds were present only to the 
extent of 0.9 per cent, in D. sac char al is and 0 3 per cent, in D. canella. 

Unfortunately no data are available for the native fly parasite Lesktopalpus 
in connection with the present survey. It muBt be made clear that the fact that 
no parasitism by this insect was obtained in the survey samples does not indicate 
the disappearance of this insect. On the contrary, during the period covered by 
the survey, as stated previously, the fly was observed in the field, but its absence 
in the survey samples does indicate its comparative scarcity at the time. 

That the prevalence of this insect is affected by weather conditions there 
can be little doubt, bnt it shonld be pointed oat in addition that the only 
authoritative statement we have on its prevalence is that of Myers (1) that, “The 
Paratheresia and Stomatodcxia are together responsible for a mortality of 3.2 per 
cent, borers in cane, but they apparently do not extend activities to the small 
grasses.” 

It has been stated that Lesktopalpus {Stomatodexia) does not occur in Berbioe, 
The fly is no doubt of rare occurrence there but the writer reared this insect from 
Dmtraea at Pin. Blairmont, Berbice, in February 1922, and since then tbs 
insect has been on other occasions taken in the same locality. From localities 
east of the Berbice river there appears to be no records of its oocnrrenee. 



OTAttJl 0f TOT AXAZOH FLY IS BRITISH (JUT AHA, 1937. 


23 


On font of the fifteen estates examined hyperparasites were found. 
Sypirpemitism of Amazon Fly pttparia occurred in 27.1 per cent, of the fields 
op tbs estates on which it was found ; and 9.6 per cent, of the poparia were 
attacked. 

In this connection it should be pointed out that the hyperparasitism, occur- 
ring as it does to puparia, takes plaoe after the parasite has done its work and killed 
the host larva. The destruction of the host population to the extent of 16.0 per 
oent. (in this snrvey) has already taken plaoe. Farther, if the hyperpar&sitism is 
calculated on the whole Amazon Fly population it is only 3.3 per cent. 

The snrvey has shown also, to some extent at least, that there is a variation 
of the prevalence of the fly dne to weather conditions, and so serves to confirm 
previous observations of this nature. 

There also appears to be a somewhat uneven distribution of the fly on 
estates, and occasionally there have been severe attacks of Diatraea in fields. 
This is to be expected for some time after the introduction of a new species, and 
until it settles down in its new environment. That, since its introduction, there 
have been so few ontbreaks of Diatraea speaks well for the fly. The fact 
should not be lost sight of that the large majority of the sugar estates in the 
Colony (there are two or three exceptions) have only on rare occasions employed 
a “ borer gang” since the colonization of the estates with the Amazon Fly was 
completed in 193. r >. 

Thompson (3) tells ns that even when conditions are relatively favourable to 
the parasite the course of events may not always present a very satisfactory 
appearance and says : 

“Perhaps the most important point to remember in this connection is 
“ that daring the period which follows the introduction and establishment 
“of a species, and the time when it has reached the highest population which 
“it can attain in the area, there is an intermediate period dnring which 
“ the species increases slowly but steadily in numbers, but during which 
“ this increase may be masked by local irregularities of various kipfls, so 
“ that in one locality the parasite may appear for a certain length of time to 
“ increase with extreme rapidity, while in another it exerts absolutely no 
“ effect, after whioh it may disappear from the first locality and become 
“abundant in the second.” 

In the survey as undertaken it must be borne in mind that the data obtained 
represent conditions as found at a particular time and stage in the growth of the crop. 
It is, therefore, not to be considered as neoessarily the best that the inseot is capa- 
ble of performing or even the best that it is doing at the present time. In-Act the 
contrary Is the case for we have found fields in the present survey in which as high 
as 80 per gent, of the Diatraea saaharalis population has been parasitized, while 



24 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 1. 

18,4 per cent, of the positive fields showed parasitism of 30 per cent, and over, 
and even the canella parasitism is often higher than has been found in 
the examinations now reported upon. Had the examinations been made at a 
later stage in the growth of the crop there is more than a probability that the 
parasitism by the Amazon Fly would have been considerably higher. For that 
reason alone it would seem desirable to undertake at a later date more detailed 
examinations of a few estates extending over the whole period of the growth of 
the crop. 

That the Amazon Fly is doing good work in the sugar area the figures given 
now leave no room for doubt. There can likewise be no doubt as to the value 
of the introduction, nor that the cost of the undertaking haB been amply repaid. 

Beyond this we should not go at present, remembering Thompson’s advice 
that “ The entomologist should be as much on his guard against premature 
reports of success as against premature complaints of failure.” It is still too early 
to draw conclusions or make statements as to the future work and destiny of 
the parasite, and mere guesses, pious opinions, or statements based on scanty 
data, are of no value. i 

References. 

(1) MYERS, J. G. (1931). A Preliminary Report on an Investigation into the 

Biological Control of West Indian Insect Pests. E.M.B. 42. 
H.M. Stationery Office, Lbndon, July 1931. 

(2) Squire, F. A. (191>). Colonial Development Fund, Progress Report on the 

Present Status of the Amazon Fly in British Guiana. 
(Unpublished Report). 

(.1) THOMPSON, W. R. (19.10). The Biological Control of Insect and Plant Pests. 

E.M B. 29. H.M. Stationery Office, London, June 1930. 



PLANT LEGISLATION IN BRITISH GUIANA AND 
THE CARIBBEAN COLONIES. 


BY 

L. D. CLEARE, F.R. Ktrr.g. 

Entomologist , Department of Agriculture, British Quiana, 


Within recent years, as the resalt of research in entomology and plant 
pathology, there has come aboat a better understanding of the pests and 
diseases affecting plants and the manner in which they are spread. With the 
acquisition of this knowledge there has followed the development of measures 
for their control and prevention, and to-day there are few countries in the 
world where efforts are not made to combat such pests and diseases of plants 
as occur within their borders and to prevent the introduction of others from 
outside. 

In order to do this effectively, it has been found necessary to enact legisla* 
tion, and plant protection legislation is now almost universal. In the 
British Empire alone such legislation is extensive, and it will be seen from 
the summary which follows that ev»n in the comparatively small area which 
is dealt with here it is not inconsiderable. 

The countries of tropical America, including British Guiana and the 
British Colonies of the Caribbean, have had their full share of devastating pests 
and diseases in the past. It is not surprising, therefore, that these countries have 
enacted legislation, the aim of which is to prevent the introduction of pests 
and diseases from areas outside their borders and to control them where they 
occur within. 

In the summary given here, an effort has been made to bring together in 
a concise form the existing legislation as it affects this Colony. For convenience, 
the information has been grouped into two parts, namely : (1) that existing in 
British Guiana both as regards internal matters as well as import and export 
prohibitions and (2) that referring to the British Colonies in the Caribbean. 

With this summary it should be possible for individuals concerned either 
with the import or the export of plants and plant products, including fruit and 
vegetables, to ascertain easily what restrictions are in force with respect to 
any particular, or to all, products in the area. It should be borne in mind, 
however, that while the summary is complete at the present time, alterations 
and additions are made from time to time, so that in future it will be necessary 
always to obtain information as to any amendments which may have taken 
place sincf the compilation of the present summary. 



aobhhtwwui. mqsval m vsamm Rtnm 
BRITISH GUIANA, 


i*m 3U 


SUMMARY OF LEGISLATION AFFECTING AGRICULTURAL 

INDUSTRIES. 

1. PLANT QUARANTINE. 

I. External — Import Prohibitions. 

A. PROHIBITED ARTICLES, INCLUDING PLANTS, SOIL AND 
PACKAGES AND ARTICLES CONNECTED THEREWITH. 


Articles prohibited. 

Country of origin. 

Reasons for 
prohibition. 

Index of 
Legislation. 

Sugar canes and any plants or 
parts thereof 

Ail countnes 

Prevention of in* 
troduction o f 
disease 

Order-in-Counci l 
under Ordinance 
No. 37 of 1936 

Plants of grasses of any kind 

»» 


»» 

Earth or soil or any thing 
packed therewith 

« 



Pimento and Bay tree 
( Pimenta acris ) 

J amaica 

Rust disease 

Notioe in Official 
Gazette dated 
December 3, 1936 

Citrus material (including 
fruit) 

United States o f 
America 

Citrus canker (Php- 
(omontiH citri ) 

Order-i n-C o u n c i 1 
under Ordinance 
No. 37 of 1935 

Fruit (except plantains, nuts 
and dried, canned, can- 
died and other preserved 
fruits) 

Vegetables (except onions. 
Irish potatoes and canned 
or preserved vegetables) 

All countries except 
British Isles, 
Canada and the 
British West 
Indies not in- 
cluding Bermu- 
da and the 
Bahamas 

Moditerianean 
Fruit Fly ( Cera - 
tith capital a ) 

Order-i n-C o u n c i 1 
under Section 28 
of Customs 
Ordinance Cap. 
33 dated May 
19, 1930, as 
amended by 
0 rder-i n-Counct 1 
dated Aug. 20, 
1934 

Raw coffee 

All countries on 
the continent of 
South America 

Coffee berry-borer 
(StephaHoderes 
nampei Ferr.) 

Regulations made 
under Ordinance 
No. 37 of 1935 







*U4* tmisbims nr sxnm wiaita ahd tbs Caribbean oolojjibs. 27 


B. PROHIBITED ARTICLES, EXCEPT UNDER LICENCE. 


Article* prohibited. 

Country of origin* 

Seasons for 
prohibition. 

Index of 
Legislation. 

Sugar canes and any plants 
or parts thereof (import- 
ed by ti»e Director of 
Agriculture for scientific 
purposes) 

All countries 

Prevention of in- 
troduction o f 
disease 

Order-in-Council 
under Ordinance 
No. 37 of 11135 

Banana and plantain suckers 

» 

»» 

tt 

Haw Coffee 

ill countries other 
than South 
America 

Coffee berry-borer 
(Stephanoderes 
hampei Ferr.) 

Order-in-Counci 1 
under Ordinance 
No. 37 of 1936 

Bees and Beekeepers’ stock 

All countries 

Prevention of in- 
troduction o f 
disease 

Regulations made 
under Ordinance 
No. 38 of 1935 


C. PERMITTED ARTICLES, PROVIDED THESE HAVE PASSED 
INSPECTION BY THE AGRICULTURAL DEPARTMENT. 


Articles permitted. 

Country of origin. 

Index of Legislation. 

Garden seeds 

All countries 

Ordor-in- Council under Ordi- 
nance No. 37 of 1935 

Plants, seeds, cuttings, bulbs 
or other plant parts in- 
tended for propagation 

n 

ft 
















28 ‘ * AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 1. 

II. Internal— Control of Disease and Tests Within the Colony. 


Diseases and Pests. 


Locality. 


Index of Legislation. 


Bnmoli ft Bophorae L. Generally 

(Coconut Caterpillar) 

Mamsmius pernicionuti Stahel. North West District 
Witchbroom Disease of 
(Cacao). 


Notice in the Official Gaictte 
under Plant Diseases and 
Pests Regulations 19.% 
making these notifiable 
diseases and pests. 


2. MISCELLANEOUS LEGISLATION AFFECTING 
AGRICULTURAL INDUSTRIES. 


Measure. 

Wild Birds Protection 
% 

Government Lands 
Orchids and Haiari 

Botanic Gardens 
Agricultural Shows, etc. 


Object 


Close season ; prohibition of 
export, killing and sale 

Prohibition of export of 


Control of 


Control of public gardens and 
grounds and Government I 
Agricultural Stations and j 
holding of shows 


Index of Legislation. 

~ < — • 

Cap. 273 as amended b\ Ordi- 
nance No. 27 of 1934 

Regulation 70 of Croun 
Lands Regulations 1919 

Government Botanic Gardens 
Regulations 1936 

Ordinance No. 34 of 1935 


PLANT LEGISLATION IN BRITISH GUIANA AND THE CARIBBEAN COLONIES. 


PLANTS AND PLANT PRODUCTS, Ac., EXCLUDED FROM 

BRITISH GUIANA. 


Prohibited Importations 


Country of origin. 


Sugar canes and any plants or partb 
thereof 

Plants of grasses of any kind 
Earth or soil 
Pimento and Kay tree 
Citrus material including fruit 
Raw Coffee 

Banana and Plantain suckers 

Plants, bulbs, seeds and other propaga- 
ting material 

Bees and beekeepers’ stock 

Garden seeds 

Fruit 


All countries 


Jamaica 
U.S A. 

All countries prohibited except under 
licence. South America absolutely 
prohibited 

All countries 


All countries except British Isles, Cana- 
da and the British West Indies (not 
including Bermuda and the 
Bahamas) 



tqunmui jomsiL <* «“*“* «"“*• [K ' l 




PWJW utoisufioN m British guiana and the Caribbean colonies. 31 




32 


AGRICULTURAL JOURNAL OF BRITISH GUIANA, 


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PLANT LEGISLATION IN BRITISH GUIANA AND THE CARIBBEAN COLONIES. 35 


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84 


iGRICtrLTtJfiAL JOURNAL 07 BBltlBH GUIANA 




Plant legislation in British guiana and the Caribbean colonies. 


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CARIBBEAN COLONIES. 

SUMMARY of LEGISLATION IX FORCE RELATING TO THE IMPORTATION OF PLANTS. — (Con Id). 


36 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[IX, 1. 


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PLANT LEGISLATION IN BRITISH GUIANA AND THE CARIBBEAN COLONIES. 37 




38 


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SELECTED ARTICLES* 


PRESIDENTIAL ADDRESS * 

(Fourth International Grassland Congress ) % 

BY 

PROFESSOR R. G, STAPLEDON. 


Greenness is the subject of my address, for grass is greener and more 
variedly and more vitally green than anything in the whole wide world, and 
green is the vital colour. Young succulent grass is the prince of feeds. Over 
an enormous area of the world grass is the foundation of the agricultural 
industry, and perhaps almost everywhere it should be the foundation. Research 
may well make this possible — yes, possible everywhere. 

Grass (and when I say “ grass ” I mean, of course, grass and clover) proper- 
ly used ensures soil fertility, grass marries the soil to the animal and the solid 
foundation of agriculture is the marriage of animal and soil. That spells humus. 
While again grass properly employed counters the devastating influences of 
erosion. 

I am proud indeed to welcome you here to grassy Wales. Though Wales, 
I hasten to add, is not proud of her grasslands. Indeed, for my own part, and 
speaking as one who has spent twenty- five years conducting research on grass- 
land in Wales, I must admit I find the condition of the grasslands of this 
country as a whole, and not only of Wales, deeply humbling. Rut then Great 
Britain, you see, and to the untold benefit of some of you here present, has always 
liked to finance agriculture anywhere, everywhere, except within her own shores. 

*The 4th International Grassland Congress was held in Great Britain last year, and was 
attended by representatives from 37 different countries. 

Although the majority of the world's great grassland areas«4ie outside the tropics, yet 
grassland plays an important part in the agriculture of every country, and at the Congress the 
discussions and demonstrations brought out points <?f general application that every cattle 
owner* wheresoever he be, can take to heart. 

. mos * 1 diking demonstrations shown to those attending ihe conference 

included the changes and betterment in pastureland that can be secured by proper rotational 
the possibilities of turning to good pasture, by tillage and manurial treatment, land 
which had formerly been regarded as waste and almost valueless, and the remarkable improved 
strains of common pasture grass that can be obtained by selection and breeding. 

Professor Stapled on’s Presidential Address to the Congress deals with some of 
the general problems facing the owner of grassland, and indicates how they are being 
faced elsewhere. The owner of grassland should look on it as akin to arable land, to bear a 
crop of the proper grasses and these alone, to be manured and subject to rotational treatment, 
to be properly drained and irrigated and to be suitably fenced. As is pointed out in the 
address, a small ares of pastureland carefully tended can be many times more valuable than 
a vastly greater area of uncared-for 4 grassland ’ on which cattle run at will. 

E. B. M. 



40 


AGRICULTURAL JOURNAL OF BRITISH GUIANA* 


[IX, 1. 


I have travelled more than a little, and I know something of grasslands 
in general, but I have not travelled or seen as much as I should have liked, and 
I can express no well-informed opinions on many types of the world’s 
grasslands. 

I have, however, come to this opinion, and I believe it to be just, nay more, 
fundamental, that the only rational approach to the problems of grassland (the 
practical problems and the research problems), is the wide regional approach. 

The first necessity is to classify our grasslands, and to understand their 
interrelations, and then to work and to plan on the basis of clearly defined 
regions — natural regions. The proper use of grass and of grassland is a matter 
of systems of farming, and therefore of facilities. It is a matter essentially of 
the right implements, the right fertilisers, and pre-eminently of the right seeds. 
More than this, it is a matter ol usage and custom ; systems of land 
tenure ; methods of marketing and a hundred other things, all of which 
can only be appreciated properly and tackled successfully on a regional basis. 
What is generally essential is to discredit old fashions and to introduce new 
fashions. In this country all manner of old-fashioned clauses in leases are, for 
example, a great handicap to the introduction of new and long overdue methods. 
In the matter of seeds, the essential thing is to use the* right strain of the 
comparatively few species that really suit the needs of any well-defined natural 
region. To organise; this is by no means an affair only of plant breeding. The 
plant breeding to be of maximum benefit should, however, he conducted in the 
region it is proposed to serve. It is only by chance, for example, if anything 
we breed here at Aberystwyth suits say Natal, North America or Norway, and 
if it does appear to do so at the first flush some plant disease — a rust form, say 
— may quite decisively intervene. Exploration yes, and the bringing ol new 
species and of new genes of tried species into every region, but the selection 
and plant breeding must be conducted within the regions. What we want is 
not a world-wide interchange of commercial seeds with their limited variability, 
but a world-wide interchange of genes. It is probably nearer the truth to say 
that there is hardly a region in the whole world that has yet got the best 
combination of agriculturally useful genes in its grassland plants, while 1 make 
bold to hazard the opinion that there are many regions in tin* world that have 
not even yet got the right species to work. But of this again presently. 

1 am sure of this, however, that a general world interchange of commercial 
grassland seeds is bad for the grasslands of the world. It has admittedly done 
good in the past, it was necessary in the opening np of new countries, but it has 
also been responsible for a great deal of harm. I agree with Dr. Wilcox that 
“ nations can live at home ” in all manner of respects, and in no respect are they 
better advised so to do (and as far as possible) than in that of their grassland 
seeds. 

I have implied that the first necessity is to map and classify our grasslands, 
and this is true the whole world over* 



PRESIDENTIAL ADDRESS. 


41 


I regard this question of mapping of prime importance. We have mapped 
the whole of Wales, and my first intention was to devote my Presidential 
Address almost entirely to a detailed discussion of our methods — for I believe 
they are good methods and as methods are applicable the world over. Our maps 
are, however, on view at the exhibit, and I hope Mr. Davies, who has been 
primarily responsible for the methods and the work, and myself, will have the 
opportunities of explaining our aims and methods to those who are particularly 
interested, both around the maps and out on the hills and fields. 

So much for mapping. I shall now venture some remarks upon the general 
problems of grassland, and all said and done, the basic problems are the same 
the world over. Of necessity I shall have to be selective and I conceive it as 
being my business to generalize, and as you will all have abundant opportunities 
amongst yourselves for correcting me, 1 shall not be afraid of generalizing here 
and there on insufficient evidence. 

The outstanding feature of grassland is its complexity. It is impossible to 
isolate the factors, and I doubt if it will lead us very far if we attempt unduly 
to isolate the factors — on the farm and on the ranges all factors interact. 
Hardly ever do we attempt to grow a single grassland species by itself. 
I like to grow Loiiutn italicion by itself for winter keep, and we are here 
experimenting with growing Phleum prutnw (our S. 48) in cultivated drills 
for winter keep, but this is incidental, and cannot now be discussed. As all 
of us grow at least 2 to 3, 4 or more species together to make a swaid, 
competition always enters into the matter. And always, always, always 
there is the grazing animal. 

Soil, climate, grazing animal. Which of these three is the most important 
factor ? Most emphatically the grazing animal ! Manure right, sow right and 
manage the grazing animal ^wrong and you are nowhere. Without the grazing 
animal there would be no grassland worthy of the name anywhere in the 
world. Management is therefore the key to the solution of the whole grass- 
land problem. The real point is this, that the animal makes for itself its own 
grassland. It is because of this, that Lsay there are regions in the w^orld not 
yet using the right species (apart from the right genes of the right species). 
By management entirely alter the conditions, make good lime deficiency, make 
good phosphatic, and if necessary poatssic deficiency, make conditions above every- 
thing favourable for a leguminous plant ; make it possible to hold animals to 
the ground, and then you can begin to consider introducing and maintaining 
species hitherto unthought of. 

I believe, and I say this is not lightly or without experience, that there 
are many range areas in the world where it would pay best and where more 
stock could be carried, and that stock in better health, if about three-quarters 
or more of the area were let go wild and completely unstocked, and if real and 
tremendous things were undertaken, on well-selected remaining areas. Tn effect, 
that is what we are doing here on the Welsh hills, and we are successfully 



it AGJttCtr&TOBAL JOVmAt 0* BRITISH GUIANA, {££, 1. 

introducing proper grassland species, including, of course, wild white clover 
(trifolium repens), where such species have never before gained a footing. 
We talk about grass and grassland. No grassland is worthy o£ the name, and 
indeed is hardly worth bothering with, unless a legume is at work. Find or 
breed the right legume for every corner of the world and you have tolerably 
good grassland in every corner of the world. Make the conditions suitable for 
the legume and manage the sward, to favour the legume as well as to feed the 
animal, and everything else will be easy — the battle will be won, 

This is indeed a sweeping generalization, but prove me wrong who can, 
for not nearly enough work has been done in exchanging legumes all over the 
world, and in making conditions favourable for legumes or in breeding legumes, 

So much for the geographical problem, as I gee it ; now for the domestic 
problem, the problem that affects everybody. The domestic pioblem is clearly 
threefold. Firstly, how to produce grass at those seasons of the year when 
it is most urgently wanted ; secondly, how to use and to farm grass with a view 
not merely to maintaining, but with a view always and progressively to increas- 
ing soil fertility, and thodly , how to manage grass so tb^t the animal always 
has offered to it young, rapidly growing and succulent grass of maximum 
nutritive value. 

The whole problem, I repeat, resolves itself into management. Each of 
the above desiderata calls first and foremost for rotational treatment Rotation- 
al treatment of a farm as a whole, and of individual fields Hot at ton in tune 
and rotation m y>au>. The always doing ot something this month with a riew 
to obtaining some definite result two or three months later. Always, too, the 
need of the sward must rank as of an importance at least equal to the day -by - 
day needs of the animal. By adopting a syAem ot rotational grazing — 
intermittent with pioper periods “ on ” and proper periods “off”— the animal 
can be given somewhere every day what it requires, and the swards need never 
suffer. One further point, swards will recover from the most villainous of 
malpractices if such malpractices are not too long continued, and ij they are 
not put into operation at precisely the same tune of the yea i, year after year • 
Hence the need for rotational management all over tiie farm. Incidentally, 

I may here interject that I do not hold with using fields continuously as 
pastures or continuously as hay meadows ; to do so is an offence against the 
basal idea of rotation m tune For rotation in tune I regard as the most 
fundamental of all grassland principles, and yet, and perhaps on most grasslands, 
especially on the ranges and open hills, the management is essentially the 
same month for month, year after year, for generation after generation. 
Ridiculous folly indefinitely perpetrated in the end enforces a heavy but just 
retribution, and all over the world millions of acres stand as doleful witness 
of agricultural practices conducted on a faulty and undeviating time 
schedule. 



mmmmriAii kr>m ms. 


43 


So much in general with reference to my three desiderate, ; now for the 
particular, and I will deal first with my No, 2 Soil Fertility, for in the last 
resort on this do 41 grass when it is wanted ” and “ succulent and nutritious 
grass 99 so largely depend. 

I have said that to ensure |toil fertility wc need to marry our stock to the 
soil, and the cheapest and most effective way to do this is to plough up all grass- 
lands that will take the plough at regular intervals. Always before ploughing up 
graze as hard as possible for some months, in order to impregnate the soil with 
urine and excrement — with what Mr. Bruce Levy so aptly describes as “stock 
nitrogen.” Having turned the sod over, apply lime, harrow in, and you will 
have made and spread an admirable compost all over your field. Now do what 
you like. Cash this fertility, or some of it, where you can in a corn 
or other crop, or sow straight down to grass again and cash your 
fertility in more luxuriant grass and build up yet more fertility. 
I hold that permanent grass where it is possible and on all grounds reasonable to 
plough is wrong in theory, wrong in fact, is uneconomic and ridiculous. Of 
course, you cannot plough up all the permanent grass, grazings and ranges in the 
whole world, but with the tractor and modem implements you can plough in all 
manner of unheard-of places and under all manner of difficult conditions. 
Manifestly it would be madness to plough up many types of range country, as 
that would be to invite certain soil erosion, but such is far from true of all range 
country. And suppose you can establish a thicker sod than ever before, and 
establish it quickly, and in the non-erosion season. While with a view simply 
to the introduction ot new species, it is often sufficient merely heavily to culti- 
vate and scratch. Pray remember you can plough up and put straight down to 
grass again perfectly well, and pray remembei also that the best top dressing of 
all is that put on the soil itself at the time of sowing seeds (I am not now refer- 
ring to applications of inorganic nitrogen applied to bring grass at some wanted 
time). How often to plough up is a matter of circumstances and condition. 
Once in 100 years is better than never ; once in twenty years better still, and 
once in ten years often quite sufficient. Plough more frequently than once in 
ten years and you begin to be scientific, progressive, and a farmer in very truth, 
for then amongst other things you can begin to avail ytfurself ol the labours oi 
the plant breeder, and if you do things properly you are going to build up 
fertility at a prodigious pace You can farm on the basis of temporary leys of 
from one to six or eight years’ duration, and produce productive grass at all those 
times of the year that climatic conditions permit stock to graze out of doors. 
The production of winter grass in telling quantity is, for example, a very real 
project under the climatic conditions of this country. 

In regard to “grass when it is wanbed” and “succulent and nutritious 
grass ” I will be very brief, for I have already detained you far too long. 

The production of short, succulent grass, and at times of the y^r when 
most needed, is a refinement of pasture management that is applicable in all its 
intricate complexity only to the true grassy-clovery swards of the more temperate 



44 - AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 1. 

* 

regions — to the fields of our farm lands. It is to grass of this sort that I am 
now explicitly referring — to grass in the main consisting of the well-tried 
European species tolerant to and actually thriving best under well regulated 
heavy grazing and heavy trampling, the species that call aloud for and prosper 
exceedingly only when amply assured of stock nitrogen. 

The production of short grass is then just a matter of rotational and 
intensive grazing ; of intermittent grazing with heavy urination, followed by 
adequate periods of rest. Once a year the plants must he allowed to grow away 
to permit adequate root growth. The botanical composition of any more or less 
permanent or long-duration sward will lie a function (almost a direct function) 
of the times of the year it is grazed hardest, and of the times of the year it is 
rested. If on any field these times are the same year after year, the number of 
species will automatically become very restricted, and probably in the interest 
of the ration and of seasonal spread-over will become much too restricted and 
automatically less and less grass will be developed just when it is most needed. 
If you proceed to accentuate this time factor by applying nitrogen 
always at the same date, very soon yon will kill out the particular 
species which respond best to nitrogen applied at that particular date — such 
species or strains will be literally grazed to death So once ihore J say, never on 
long-duration swards and on permanent pastures do the same things to the same 
date programme on the same field for over two years in succession — rotation in 
tune again ' It is often a very sound practice to adhere to a time schedule for 
two or even three years in succession on short leys (leys ol up to three years’ 
duration) for when you have ruined such leys you plough them up. Hence one 
of the outstanding advantages of short leys. Short leys are intended to do a 
certain thing, and when they will do this thing no longer you plough them up — 
and I daresay that is about the best of all rules for the management of the grass- 
lands of our farms. 

Short grass at different a> <! at all tmm of /hr gear, and especially at the 
most difficult times — that is my last point, and I think the most important point 
of all, and it is one that offers tremendous scope for detailed research. 

There are two main avenues ol approach, the one by employing special 
seeds mixtures designed in the main to cater for a particular and short period of 
the year (once more the glory of comparatively short leys, and the justification 
of the plant breeder), and the other so to manure and so to rest particular fields 
that they do in fact have grass to offer at the particular date demanded by the 
grazing schedule. 

I will give two examples of special “ time ” seeds mixtures. At this Station 
we advocate comparatively simple seeds mixtures, and we have achieved great 
success with one consisting only of our Station bred leafy perennial rye-grass 
(Loliwn perenne) (Dr. Jcnkin’s S. 23), rough-stalked meadow grass ( Poa tririalis ) 
and wild white clover {Tnjoliwn repent*). In some years the sward so produced 
(as is common with L. perenne) tends to go short in July and August. We have 



PRESIDENTIAL ADDRESS. 


45 


however found that another excellent simple mixture is one made up of our 
Station bred meadow fescue (Festuca pratenws) (S. 53) ; Dr. Jenkin’s pasture-hay 
timothy (. Phlemn pmtenw) (S. 48), and wild white clover ( T repens ) ; this gives 
palatable and productive grazing all through the season, and in July and August 
considerably outyields the L. pwenue mixture. A mixture consisting of our 
Station bred Alopecurus pratensis (S. 5(5) ; our Station bred red fescue (Festuca 
rubra) (S. 59), and wild white clover ( T . repen •<) remains wonderfully winter- 
green and gives an unusual amount of leafage in late February and during 
March — that is to cater for the winter. 

As to resting for particular periods, I will take as my example the pro- 
duction of winter grass in this country, for our climate permits of out-winter- 
ing. We in this country are now drying spring and summer grass for the 
winter, and I am inclined to say why not grow winter grass for the winter and 
convert it in situ ? It can be done already, despite the fact that the plant 
breeder has hardly begun to show his hand in this matter. 

What is wanted is winter-green strains and then the plan is to rest the 
fields completely as from about the middle of August or not later than towards 
the eud of September. By the use of proper strains, resting at the right time 
and properly manuring, we here at Aberystwyth have obtained grass in situ 
available from Christinas to the end of March, with a crude protein content of 
trom about 14 to as high as 20 per cent, of the dry matter. The yield per acre 
of this sort of grass then available has on occasion exceeded 3,500 lb. of dry 
matter. Thus with a range of fields a great deal of grass of high quality can 
be made available all the winter. Much better winter grass, and more of it, 
can be obtained trom young leys sown with the right strains than from per- 
manent pastures. 

In our experience much better winter grass is obtained by resting a 
pasture which has been heavily grazed and saturated with stock nitrogen for 
some time than from an aftermath. If aftermath is wanted for winter grass 
such aftermath should not he allowed to grow straight on from after hay 
harvest, but the field should be grazed heavily as soon as it will hold stock after 
harvest, given a dose of 4 ‘ stock nitrogen ’’ in fact, and then put-up for winter 
grass. At the time of putting up for winter grass we always dress with about 
1 cwt. to the acre of nitro-chalk — as a supplement to stock nitrogen inorganic 
nitrogen is invaluable. 

I have rather daringly covered a very wide field, and I have (although 
partly in the interest of brevity) most daringly generalized. I am sure you 
will appreciate the fact that anything of truth or value that I may have been 
able to say is due almost entirely to the untiring efforts and competency of my 
colleagues, They do the work, I do the talking, i am afraid I have talked 
almost solely around my own experiences and the work of my own* Station. 
But nevertheless, and however unworthily expressed, I think I have said 
enough Vo justify the belief that ell of us here present are engaged in the study 



46 AGRICULTURAL JOURNAL OF BRITISH GUIANA. £tX, 1, 

of a very great science ; oar concern is, however, much more than that 4 w® 
are concerned also with a very great art, and more still, this oar enterprise is 
of prime sociological significance and importance. 

If the peoples of the world, and to a man, are indeed to be adequately fed 
with fresh food of the highest quality, and balanced in every respect, then the 
enormous acreage of the world that stands in grassland of every character, 
and of no character at all, must be brought to play its full part. It is not only 
grass itself that is so essential as a feed, hut it is the whole acreage under grass 
that must be made to yield to more intensive treatment. To an ever-increasing 
extent this acreage must be made to produce better and better grasB, and also 
other necessary crops. 



THE BOEING POINTS FOR REFRACTOMETRE TESTS 

OF SUGAR-CANE.* 

BY 

C. CAMERON, 

Field Manager, Sugar Experiment Station 
AND 

H. B. SINGH, 

Laboratory Assistant. 

The Zeiss Ref ractometer has been adopted in British Qniana for the purpose 
of testing sugar-cane fields prior to harvest, and of guiding the selection and 
discarding of seedlings at the cane-breeding station. Under the latter 
conditions it was soon found that while the co-efficient of correlation was 
high between the brix of expressed juice and the total solids as determined 
by refractometer readings on composite samples from borings made in the top, 
middle and bottom thirds of the stalks, the absolute values did not correspond as 
closely as was desirable. An investigation was therefore undertaken to determine 
if there was any fixed point or points in the stalk which would yield a refrac- 
tometer reading identical, or nearly so, with the true mean brix of the stalk. 

The work was carried out on plant canes of three varieties (P.O.J. 287b, 
Diamond 10 and D. 06/30) and in duplicate on each variety. The procedure 
adopted was to select from the same field of any one variety, five stalks having 
eleven internodes (joints), five having twelve internodes, five having thirteen 
internodes, Ac., Ac. On arrival at the laboratory, the tops (cabbage) of the 
stalks as far as the first joint below the point of attachment of the oldest green 
leaf-sheath were discarded. Then for each batch of five stalks the internodes 
were milled separately, i.e., the five topmost (second) joints together, the five 
next joints together and so on until the bottom or older end of the stalks was 
reached. 

The per cent, total solids in juice for each batch of joints was determined, 
and by noting the weight of the juice extracted it was possible to calculate a 
weighted mean total solids for the whole stalk. All that was then necessary 
was to note at which joint or joints the per cent, total solids corresponded with the 
mean figure for the whole stalk. The results obtained are presented in Table I, 

It will be seen that in stalks of all lengths from fifteen to twenty -four 
internodeB (joints) and of all three varieties tested, the per cent, total solids 
of the juice from the seventh or eighth joint below the point of attachment 
of the lowest green leaf-sheath corresponds closely and consistently with the 
mean total solids of all the juice from the stalk. 

•Reprinted from Tropical Agriculture, Vol. XIV, No. 11, pp 313-310, 1937, 



48 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 1. 

In the case of the shorter (younger) stalks, having from eleven to 
fourteen joints, the locatipn of the joint with the true mean total solids is some- 
what higher up the stalk, />., at the fifth and sixth joint below the point of 
attachment of the oldest green leaf -sheath. 

In the longer (older) stalks a joint near the bottom of the stalk (about 
the sixteenth to the eighteenth joint below the point of attachment of the 
lowest green loaf-sheath) also tends to yield a juice whose total solids 
corresponds with the mean for the whole stalk, but the exact joint cannot be 
defined with as much accuracy as the higher one and does not appear to 
occur at all in the younger stalks. 

Table II shows a typical set of readings for two groups of five canes. 
They show that the difference in total solids between the fifth and sixth 
joints, or between the seventh and eighth joints is slight. Observers can there- 
fore decide on a definite point (say the sixth joint for canes having from eleven 
to fourteen joints and the eighth joint for canes having from fifteen to twenty- 
four joints) and expect a reasonably high degree of accuracy in the results. 

t 

An investigation of this nature incidentally reveals what point of the cane 
stalk has the highest solids content. It was found that as far as the* shorter 
canes (11 to 14 joints) are concerned, this is located at the base whereas in canes 
with longer stalks (15 to 24 joints) it tends to occur approximately in the middle 
of the stalk. 


TABLE I. 

Loc vtjon of Jojvr* or Cv\l Hr \lk^ with it.k <l\t Toial Holid^ coiuiW’omhno 
to Mi v\ Total Solii^ or Emjkl Hialk. 


S'JALK or 


Number of Joint Below the Poiut of Attachment of the Oldest Green 
Leaf winch may be Boied to Secuie a Refractometer Reading 
Corresponding to the Weighted Mean Solids of the Whole Stalk, 


11 

Joints 



5.57 

±0.10 



12 

do. 



5.83 

=±=0.15 



13 

do. 



7.00 

±0.25 



14 

do. 

• •• 

1 1 9 

0.25 

±0.68 



15 

do. 



7.87 

=*=0.28 



16 

do. 

9 • 4 

... 

7.28 

±0.33 



17 

do. 

• • • 


8.11 

±0.53 



18 

do. 

• • 9 


7.75 

±0.29 



19 

do. 

• •• 


7.89 

±0.35 

1G 7 

±0.63 

20 

do. 

• « 


8.89 

±0,46 

15.5 

±1.06 

21 

do. 



7,85 . 

±0.60 

18.0 

±0.62 

22 

do. 



7.25 

±0.42 

16.3 

±0.G1 

23 

do. 



7.25 

±0.76 

17.0 

±1.00 

24 

do. 


*'* 

8.14 

±0.59 

18.0 ! 

j 

±1.17 


THU BORING POINTS FOR REFR A CTOMETER TESTS OF SUGAR-CANE 49 


TABLE II. 

Two Tyhioal Series of Refhactometer RnimNfis, 


Joint No. 

Five 12- Joint Stalks of D. 06/30. 

Five 21-Joint Stalks of Diamond 10, 

Refrac- 

tometer 

Solids. 

Total 
Weight of 
Juice from 
5 Joints, 
lb. 

Total 

Solids from 
Juice, 
lb. 

Refrac- 

tometer 

Solids. 

Total 
Weight of 
Juice from 

5 Joints, 
lb. 

1 

Total 
Solids in 
Juice, 
lb. 

1 

This Interno 

de was discar 

ded with top 

; 12.450 
12.675 

12 975 
17.8(H) 

18 000 
18.4(H) 
18.4(H) 
14.025 
14175 
9.550 
4,925 

Total ~ 
153.375 

(cabbage.) 



2 

5 

4 

5 

6 

7 

8 

9 

10 

11 

12 



ccni^xxx xodaioi : : : : : : 

\ 

0.75 

0.75 

0.75 

! i.oo 

, 1.00 

1.00 

1.00 

0.75 

0.75 

0.50 

0.25 

18.8 

17.8 

18.5 

19.0 

19.2 

19.2 

19.0 

18.9 

19.0 

19.8 

20.2 

19.8 

19.8 

19.6 

19.8 

19.6 

19.2 

19.4 

19.7 

19.8 

0.75 

0.75 

0.75 

0.75 

0.75 

0.75 

1.25 

1.00 

0.75 

0.50 

0.50 

0.75 

1.00 

0.75 

0.75 

0.75 

0.50 

0.50 

0.50 

0.50 

14.100 
13.350 
13.875 
14.250 
14.4(H) 
14.400 
23.750 
18.9(H) 
14.250 

9.900 

10.100 

14.850 

19.8(H) 

14.700 

14.850 

14.700 

9.600 

9.700 

1 9.850 

9.900 

13 

14 

15 

1C 

17 

18 

19 

20 

21 

Total — 
8.50 

Weighted ] 
Mean | 
( Refracto- i 
i meter 

1 Solids - . 

I 18.04 , 

1 ___ 1 






Total - 

Total™ 





1 

14.50 

279 225 

1 

| 





Weighted 


i 





Mean 


! 





Refracto- 


i 

i 





meter 


! 





Solids =* 


! 

i 





19.26 



Summary. 

An investigation to determine whst joint or joints in a sngar-cane stalk bad 
a total solids content corresponding with the weighted mean total solids of the 
entire stalk is described. 

It is shown that under British Guiana conditions an accurate reading may 

he obtained from the fifth or sixth joint below the point- of attachment of the 

oldest green leaf-sheath in the case of canes having from eleven to fourteen 
joints ; and the seventh or eighth joint in the case of canes having from* fifteen 
to twenty-four joints. 





50 


AGRICULTURAL JOURNAL OR BRITISH GUIANA. 


It is also shown that no corresponding joint with the mean total solids 
occurs in the lower (older) portion of the Btalk of canes having from eleven to 
eighteen joints, but that such may be fonnd in the canes having from nineteen 
to twenty-four joints. The location of this joint is, however, more reliable to 
fluctuation, and observers may better rely on the joint with the mean total solids 
in the upper portion of the stalk. 

Acknowledgments, 

The writers are indebted to Mr. 0. Holman B. Williams, Agronomist in 
charge of this Station, for his advice during the progress of the work and his 
suggestions with regard to the presentation of the results. 



COFFEE QUALITY 


The task of elucidating the factors that govern coffee quality is beset with 
difficulties. Good field husbandry and factory practice can contribute much in 
giving the desired size, colour and evenness to the raw coffee ; the special 
requirements of the roast are more difficult to attain, whereas little is known of 
the conditions that make for the desired acidity, body and flavour of cofl’ee in 
the cup. The main difficulty in correlating the liquoring properties of coffee is 
that it has not been possible to define liquoring properties in chemical term?. 
The personal equation of the taster also plays an important role, thus making it 
difficult to standardize any coffee samples under consideration. 

The scientific literature on the subject of coffee liquor is scanty and not 
very helpful, as it usually gives no useful clues that may lead to direct methods 
of investigating the true meaning of differences in the liquoring properties of 
coffee. Such differences, which often vary greatly between neighbouring 
estates, play a profound part in the economy of coffee production, more especially 
in East Africa, where such a wide range of prices obtains. The necessity for 
making some progress towards the solution of this intricate problem has now 
become urgent. 

The outlook for making early progress by studying the nutrition of the 
coffee tree or by comparing bean analyses with unstandardized terms of liquor, 
offers little promise. It is therefore pleasing to read an account of some head- 
way in the matter of elucidating coffee quality that has been made by investiga- 
tors in Brazil and Costa Rica. ' The purpose of this note is to draw social 
attention to these coffee quality investigations and to discus*, their possible appli- 
cation to the coffees of East Africa. 

An account of certain Brazilian investigations dealing with the effect of 
harvesting and factory methods on coffee quality may be summarized as follows: — 

1. When cherries were allowed to dry slowly on the tree in normal, harsh, 
or “Rio-flavoured" regions, the resultant coffee was harsh, whereas similar dry- 
ing on the tree in recognized mild-flavoured areas gave a mild coffee. With such 
slow drying of the cherry, the specific natural flavours are retained in the 
properly prepared coffee, 


* Reprinted from East African Agricultural Journal, Vol, III, i— September 1937 

*" Recent Efforts for the Improvement of Brazilian Coffee”, in the Month} y'Bulletm of 
Agricultural Science <£■ Practice, Int Inst, of Agric., Rome ; January 1937. 



52 


AGRICULTURAL JOURNAL OF BRITISH GUIANA* 


[IX, 1. 


2. It was found also that cherries from regions known as good gave a coffee 
of mild beverage only when subjected to correct harvesting and factory treat- 
ment This consists in the main of slow drying with constant stirring of 
completely ripe-picked cherries such that no fermentation of the pulp occurs . 
When such correct methods were neglected, and mixed stripped cherries, even 
from regions famous for high quality, wore allowed to ferment in the pulp, the 
resulting coffee was inferior in beverage. In the above two investigations it will 
be noticed that the coffee was prepared by the normal Brazilian method of dry- 
ing the coffee in the cherry and then decorticating. 

3. Another investigation compared the quality ot coffee from different 
sources, when prepared by pulping the cherries and then washing and drying the 
beans. It was found that all samples pulped, from every region, always gave a 
mild beverage. The control samples, which were not pulped but were allowed 
to ferment in the cherry, gave a beverage with a disagreeable flavour varying 
with the degree of fermentation that had taken place. 

4. A further test in tracing the harsh or mild quality of coffee was carried 
out by spraying cherries ot known poor quality, while on the tree, with a sugar 
solution containing cherry yeasts which are normally associated with high 
quality. It was found that there was a difference in the quality of the coffee 
from the sprayed trees. The sprayed cherries never had the harsh or “ Rio ” 
flavour. 

5. The effect of inoculation with a more suitable micro-flora was tested by 
adding the pulp of cherries from a plantation yielding mild coffee to fermenting 
cherries from a plantation known for its “ Rio-flavoured ” products. It was 
found that the resultant coffee had a pronounced mild flavour. 

In the Costa Rica investigations, using the wet fermentation method of 
preparation, it was found that when pulp from a superior quality coffee was 
added to another fermenting pulped coff ee, the resultant beverage was of a higher 
quality. 

It had been thought that the harsh or “ Rio " flavour, characteristic of coffee 
originating from certain defined regions in Brazil, was due to the nature of the 
soil. The above investigations, carried out independently in Brazil and Costa 
Rica, showed that by proper treatment it is possible to produce mild coffees in 
the regions hitherto known for their hirsh coffees. It has been s)iown that 
the nature of the fermentation and the resulting quality depend largely on the 
specific yeasts that predominate in the micro-flora of the coffee cherry. 

It is supposed that the products secreted by the organisms in the pulp have 
a profound influence on the quality of the coffee bean, as the cell wall of the 
latter is more or less permeable to secreted ferments. It is believed that the 
yeasts secrete a ferment which penetrates the beans and provokes the mild 
flavour, or else that they secrete something specific which inhibits the activities 
of other less suitable organisms which are normally responsible for the harsh 
“ Rio ” flavour. 



COFFEE QUALITY 


53 


A survey of the predominant micro-flora, in good and bad plantations 
respectively, showed which were the most beneficial, and pure cultures were 
separated out. It has been shown that when such pure cultures of yeast 
are added to previously sterilized cherries, the fermenting processes and also 
the resulting flavour of the beverage are altered. The practical application of 
this study lies in altering the micro-flora living on the cherry and thus forming 
associations in which the beneficent yeasts of high quality coffee predominate. 

It will be appreciated that the above-mentioned results, quoted by M. 
Rogerio de Camargo of Brazil and Dr. ('. Ricardo of Costa Rica, offer a direct 
line of approach for investigating variations of coffee quality in East Africa. 
They appear to offer more promising lines of approach than bio-chemical studies 
of the metabolism of coffee bushes and analyses of coffee beaus, when one con- 
siders that analytical data need not necessarily explain the finer differences in the 
liquor of samples of coffee. Again, field and factory trials involving inoculation 
with the predominant micro-flora living on certain cherries or pulp are such that 
they can be initiated in a simple manner. Then, if these tests show sign of 
promise, they could be followed up with a field survey of the types associated 
with good and bad liquor and pare cultures of beneficial micro-flora could be 
separated out. 

Lest the above investigations should lead to too optimistic views being held 
about the possibilities in East Africa, it might be well to refer to some of the 
major difficulties involved. In the first place, the woik dealt mainly with the 
extremes of harsh 01 “ Rio-ilavom e<l ” coffee against Brazilian mild coffee, 
whereas here we have to deal with differences of liquor within a series of mild 
Arabica coffees. The Brazilian investigations again deal largely with coffee that 
is stripped off the trees, dried and decorticated — it being found that pulped and 
washed coffee always gave a milder flavour. However, work in Costa Rica has 
shown that the addition of selected pulp can improve the quality even of coffee 
prepared by the wet method, so that it may be found that fermentations produced 
by various micro-flora may have an effect even with the East African mild series. 

Those working on coffee in East Afrioa are indebted to the American work- 
ers for thus indicating a possible direct line of approach in investigating the 
quality of local coffee, aud it is to be followed up by the Kenya Coffee .Team 
with the coming crop. 



NOTES. 


Bronze-Leaf Wilt Disease of the Cooonut Palm.— For many fears 
past coconut palms in Trinidad have suffered from a disease to which the term 
“ Bronze Leaf Wilt ” has been applied. The Department of Agriculture recently 
published a bulletin prepared by F. M. Bain on this subject. Thousands 
ot palms have died as a result of this trouble, and the position as regards 
coconut growing is such that, with the exception ot estates situated on the more 
favourable sandy coastal belt, large tncts of coconuts in many areas are 
threatened with extinction within the next few years. This disease occurs in 
British Guiana and is responsible for the loss of many trees on soils unsuitable in 
regard to texture. 

DESCRIPTION OF THE DISEASE. 

The usual age at which trees die from the disease is fifteen to eighteen 
years. The three lowest leaves of bearing palms, which usually appear quite 
normal and healthy previously, are observed to have taken on a yellow and 
bronze colouring, the colour proceeding from the tips ( of the leaflets backwards. 
At the same time the tips of the next two or three leaves are seen to be yellow* 
ing, the extent Qf discoloration increasing with increase in the age of the leaf. 
The yellowing of the leaf extends up to still younger leaves, but long before 
the youngest leaves show discoloration of any kind a rot sets in at the base and 
in the folds on the leaflets of the central spear of leaves. The rot later extends 
into the cabbage. This rot develops to a considerable degree before the central 
spear of leaves changes colour, but in the later stages of the rot they wilt, 
turning a dull greyish-brown colour and fall over at the base. Shedding of 
nuts takes place at the same time or slightly in advance of the discoloration of 
the leaves ; the youngest nuts being shed first. The oldest inflorescence on 
the tree is seen to be changing to a brown colour, in some cases even before the 
spathe has opened. 

In some instances palms which have shed their nuts are to be seen with 
healthy inflorescences. This occurs after an extended drought period and then 
palms recover with the advent cf the rainy season. Such palms may be found 
in situations where “ Bronze Loaf Wilt ” does not occur. 

It will be seeu that the external symptoms of this disease are identical 
with those of “ Red Ring”, which was shown by Nowell to be caused by the 
nematode Aphetcnchus cocophlus. 

SOIL STUDIES. 

In 1928 Briton-Jones suggested that a soil factor is responsible for the 
diseaset since both he and Nowell were unable to associate any organism with 
the disease except as a secondary infeotion. Soil studies therefore formed the 
basis of this investigation. 

A general soil survey gave no definite correlation between soil type and 
Incidence of the disease. Examination of soils from “ Wilt ” and “ Wilt*free ,f 



NOTES. 


55 


areas for texture, organic matter, nitrogen, carbon : nitrogen ratio ami available 
phosphate showed no marked differences. Generally speaking, the soils of the 
good ooconnt areas show more available potash than those of the “ Wilt” areas, 
but the difference was not sufficiently large or consistent to account in itseli for 
the disease. Weekly fluctuations in soil moisture, soil niti ate and water table 
were studied over a period of eight months, which included both wet and dry 
seasons, but abnormally wet weather during this particular period detracted 
from the value of the results. Further moisture determinations, however, 
during more normal weather, gave indications of a greater conservation of 
moiBture in the sub-soils of healthy areas than in the contrasted wilt areas. 

Consideration of the physical conditions and allied water relationships of 
the soil led to a classification of wilt soils which clarified the problem con- 
siderably. Three types were recognised : 

I. Surface soil is close textured aud overlies a sub-soil which is im- 
pervious to water. Such a soil is subject to waterlogging during wet 
periods and liable to dry out quickly in the surface soil during 
periods of drought. 

II. (a) Soil and sub-soil are opeu-textured and free-draining. This leads 
to a relatively poor water supply during dry weather. 

(b) Soil and sub-soil are compact and dry out quickly in times of 
drought. 

III. Friable top soil with an intolerant sub-soil layer. 

ROOT STUDIES. 

(a) Root system of trees in healthy area : root development in the 
first foot was very great, many branch roots and feeding rootlets being 
observed. The number of roots decreased graduallj in the second and third 
feet but was still appreciable. In the lower depths to six feet there w ere still 
roots to be found, the majority within a six-foot radius of the bole. 

(b) Root system of trees on soils of Class I : root development in the first 
foot was very good, many feeding rootlets being observed. In the second and 
third feet, the development was generally good, but in some instances a few 
rotting roots were observed near the bole of the tree. Below this layer the 
soil was waterlogged and a mass of rotted roots was encountered. 

(c) Root system of trees on soils of Class II : root development in this case 
was observed to a depth usually about four feet. The numbers of main and 
branch roots as well as feeding rootlets were much less than in the case with 
trees growing in healthy areas. The depth of penetration was also much less. 

(d) Root system of trees on soils of Class III : this class refers to soils of 
the Princes Town Marl type. Root development is comparatively good until 
the marl layer is reached. Very few roots penetrate mto this layer. Where 
wilt oconrs the marl layer is usually at a depth of two or three feet. Where 
the layer 4s deeper, wilt is apparently not very prevalent. 



S6 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, t 


LEAF ANALYSES. 

Leaf samples Were collected for analysis to see whether any differences in 
the nutrient status of plants growing on contrasted healthy and wilt areas 
could be revealed. It was found that, in general, the nitrogen status of palms 
in wilt areas tends to be higher, and the phosphate status lower, than for palms 
in the healthy areas. 

CAUSE OF THE DISEASE. 

In considering the soil data, the physical nature of the soil was found to be 
the most important factor. From general field observations, incidence of the 
disease is most marked during period of drought, but measurements of the avail- 
able soil moisture in the top two feet of contrasted healthy and wilt areas brought 
out no differences sufficient to explain the disease. It appeared, therefore, that 
any difference must occur in the soil below two feet. Root studies showed 
differences in the plants grown in the various soil classes, and indicated that the 
water relationships were such as to hinder root absorption at certain periods. 
Previous to wilting, the palms show very tine vegetative growth, and this 
explains their high nitrogen status, as found by leaf analyses. 

The disease can now be explained on all three soil types ; 

Class I Soils — Close textured surface soil overlying an impervious sub-soil, 
At the beginning of the rains the trees increase their absorption of water and 
nutrients, giving'good growth and a healthy appearance. As the rains increase the 
impervious nature of the sub-soil causes a temporary water table to be formed. As 
this water table rises the subsurface roots are submerged, and finally die 
and rot. The surface roots, however, continue their absorptive function. 
During the ensuing dry period the surface soil dries out rapidly, and roots in 
this area can function at most very feebly. In the sub-soil, where there is 
ample moisture, roots have been killed out and hence no absorption can take place. 
The result is water deficiency in the plant, which, combined with the increased 
transpiration during dry weather, causes “Bronze Leaf Wilt”. During its youth 
there may be sufficient moisture all the year round to satisfy the requirements 
of the tree, hence “supplies” on this area look promising. 

Clas s II Soils — Surface soil and sub-soil open textured and free draining. 
During rainy periods there is a constant supply of water, and absorption pro- 
gresses favourably, but during a prolonged drought the soil dries out rapidly 
to a great depth, and the water supply may be reduced to the wilting point. 

Class III Sods — Friable topsoil with intolerant sub-soil layer. General con- 
ditions are similar to those of Class I soils. Palms make exceptionally good growth 
in the early years, but the root system is restricted by the intolerant layer and 
a stage is reached where it cannot meet the nutrient requirements of the tree. 

METHODS OF CONTROL. 

Class I Sods -* *More efficient drainage, and trenching with organic material* 
Would produce a more even supply of soil moisture throughout the year* 
Where such treatment is uneconomic, a change of crop is recommended, sugar 
cane being the most suitable substitute. 



NOTES. 


57 


Cl axs II Soils — Where possible, irrigation should be practised, but 
conservation of the soil moisture might be attained by trenching with pen 
manure, husks and other organic matter. In view of the poor nutrient status of 
these soils, the application of fertilizers, particularly potash, is recommended. 

Class III Soils — The depth of the intolerant sub-soil layer is the controll- 
ing factor, and no economic remedy can be suggested. Where coconuts are 
not profitable another crop should be grown. D.W.D. 

Rotenone Yielding Plants of South America. — A most interesting paper 
on these plants by B. A. Krukoff and A. C. Smith has recently been published in the 
American Journal of Botany (Vol. 24, No. 0, .'>711-587, November 1937). These 
workers have had many opportunities of examining in the field the species of 
Lonchocarpus, etc., from which the natives of different parts of South America 
extract fish poisons, and some of which have recently acquired a commercial 
value on account of their content of rotenone and other extractives which are 
valuable as insecticides. As a result of their collections and observations they 
have now been able to make an important contribution towards the correct 
botanical determination of these plants, which have hitherto puzzled botanists 
working only with Herbarium material. Owing to the facts that some of the 
species of Lonchocarpus are seldom found in flower, that the species concerned 
are much more numerous than was realised by early workers, and that consid- 
erable variation may exist in leaf characters of the same species when the leaves 
examined are from old or young portions of the same plant, or from plants grown 
under different conditions, it has been impossible for systematists working with 
scanty material to distinguish correctly the different species concerned. 

In their paper, Krukoff and Smith describe one species of Derris, and nine 
species of Lonchocarpus, including three new species which are described and 
named, and two species, the vegetative features of which are described but which 
in the absenoe of flowers cannot yet be named. 

The cultivated barbasco or cube of the Amazon basin, known in recent 
years as Lonchocarpus nicou (Aubl.) DC, has been recognised as differing from 
the original plant described by Aublet on which the species was based, and has 
been named L. atilis A. C. Smith, sp. Nov. The other important rotenone 
yielding plant of this area, timbo, is Lonchoccupus urucu Killip and SmitJv 

Of more immediate importance to this Colony is the recognition that the 
Haiaris, recently considered also to be Lonchocarpus nicou and therefore con- 
specific with the powerful poison plants of the Amazon basin, are in fact different 
species, thus readily accounting for the fact that they have a very much lower 
rotenone content than cube. The White Haiari, which is found throughout 
British Guiana, has been named L. Marty nil A. C. Smith sp. Nov., and the 
Black Haiari, which appears to be well distributed in both Surinam and this 
Colony, is recognised as L. Chrysophyllus Kleinh., though it is possible that this 
name may have to be revised when further flowering and fruiting material, 
whloh is very rare in the oase of this species, has been found. 





5S AGRICULTURAL JOURNAL Of BRITISH GUUXA. 

Surinam and Curacao* — In the Times Trade and Engineering of December 
1937, Dr. M. van Blankenstein writes an informative article on these Dutch 
colonies in the Caribbean. Surinam is a part of the South American continent, 
with British Guiana, French Guiana and Brazil at its boundaries. Except for the 
narrow, populated strip along its coast it is coyered with jungle and savannah. 

The soil of the populated area is fertile. In the interior many valuable 
tropical woods are found. Gold deposits, which have been exploited more or less 
successfully for many decades, are found in widely scattered parts of the land in 
the form of veins in rocks or in the mud of creeks. The most important source 
of income for the country is, at present, another mineral — namely, bauxite, raw 
material for the manufacture of aluminium. High-grade iron-ore is also found 
in Surinam. Rivers facilitate transport across the populated area, which, how- 
ever, has only 150 miles of serviceable roads. 

In the eighteenth century Surinam was a source of wealth for the Nether- 
lands. The beautiful patrician houses bordering the canals of Amsterdam are 
built with money derived more from Surinam than from the East Indies. There 
was an old and exceedingly rich class of plantation owners in Surinam who had 
immigrated during the seventeenth century. Their descendants are still in Suri- 
nam, but by the beginning of the nineteenth century they had lost most of their 
wealth and in many cases their plantations. The cultivation of cotton and sugar 
was ruined, that of cotton coming to an end with the competition offered by 
North America, while other agricultural activities languished after the abolition 
of slavery in 1863, not so much because of the abolition itself as owing to the 
bad management which lollowed it. 

From this time onward Surinam has been struggling with a population 
problem. The country is as large as Java ; but Java has now 45,000,000 inhabi- 
tants while Surinam has only 165,000. There are many different races of people. 
With the abolition of slavery, Chinese were imported as workmen. Many of them 
remained in the country and today they constitute 1£ per cent, of the population 
in the form of a middle-class. Later British-lndians were imported in great 
numbers and many of them, too, have climbed up into the middle-class, but since 
1918 British-Indnn labour has no longer been obtainable. Nevertheless the 
British-lndians constitute 27 per cent, of the population. Of much importance 
are the Javanese, who, when their contracts have expired, either return again to 
their native country or receive a holding as small farmers in Surinam. They 
already form 23 per cent, of the population and their number is increasing. The 
majority of the people of Surinam is, therefore, Asiatic. 

This large country with its small population has for many years cost 
Holland more than 3,000,000 guilders a year in the shape of various contribu- 
tions, and the revenues do not offset this expenditure. Many enterprises Which 
have been started have turned out to be unsuccessful. How the old agricultural 
prosperity collapsed has already been told. The cocoa-tree promised, at the 
beginning of this century, new wealth to the country, but when everything was 



NOTES. 


59 


t h riving ft devastating disease (Witch Broom) affected the trees and put an end 
to all hope. Subsequently the banana promised to bring prosperity, lmt another 
epidemic ol disease (Panama Disease) completely destroyed the plantations. 

One failure followed after another and the country suffers from lack of 
population. The beautiful wood in the forests cannot be systematically exploit- 
ed ; the iron ore is not transportable ; and for balata there is little demand. The 
gold, too, has brought with it many bitter disillusions. There is no better 
characterisation of Surinam than as the land of great but economically unexploit- 
able possibilities. Hopes are now focused once again upon banana cultivation 
and upon the export of citrus fruits which thrive well in this country. 

Although “ negro-English,” the language of the slaves, is still the language 
of the lower classes and the “ lingua franca ” of the islands, the whole popula- 
tion and even the Negro and Red Indian children are educated in the Dutcjh 
langnage. Education is compulsory and the primary language employed by 
schools is Dutch. The non- Asiatic population is chiefly of the Protestant religion. 

The Antilles. 

The Antilles, a group of islands with Curacao as the main unit, offer a 
great contrast in all respects to Surinam. The earth is barren, water is scarce, 
and there are no mineral deposits. The native language is Papiamento, a 
Spanish dialect. The population is Roman Catholic. There has been no im- 
portation of Asiatic peoples worth mentioning. Since the conquest of the 
island from the Spanish in 1636, Curacao has remained Dutch territory. Like 
Surinam, the colony was long poor, and only less expensive to the Motherland 
because of its smaller population and smaller area, but when the Shell and 
Standard Oil groups established there their great refineries for Venezuelan oil, 
a period of prosperity began for Curacao. Even the great world economic crisis 
could not affect it seriously. It is Curacao’s advantageous position in relation 
to the Panama Canal which has made this development possible. Curacao 
eclipses Amsterdam many times in the volume of shipping directed to the port, 
and in terms of tonnage Curacao is now the second seaport in the Dutch Empire. 
The oil industry and shipping maintain the entire population. The colony is no 
longer cause for budget worries. 

Both the West Indian Colonies belonging to the Kingdom of the Nether- 
lands have, therefore, their tradition. The Dutch people have become accus- 
tomed to spend with inexhaustible resignation a great deal of money on Surinam, 
poor but nationally closely connected with Holland, and to hear of nothing but 
prosperity in, connexion with Curacao. 


Soil firOftion,—- The following are two extracts from a recent article by Sir 
Frank Stock dale, K.O.M.G., K.B.E., in the Emp. Jour. Exptl. Agr. } October, 1937, 
on the problem of soil erosion : — 



60 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 1. 


West Indian Dependencies. 

Very little attention has been given to soil erosion in these dependencies 
and generally speaking the loss of soil from this cause has not been as excessive 
as it has been elsewhere, mainly because clean weeding has never been adopted 
as an agricultural practice, and planting in holes has been general. Sugar-cane 
is planted in holes or furrows, and in the cultivation of many food crops the 
system of preparing holes and mounds is fairly common. In some of the 
mountainous islands with heavy rainfall, erosion has, however, been serious, and 
it has recently been recognised, in St, Vincent for example, that considerable 
erosion is taking place. In Jamaica, moreover, the position is serious in the 
Blue Mountain range, and has not received the attention it deserves. It is, 
indeed, fortunate that the calcareous soils ot Jamaica do not erode readily as 
little or no attempt is made to check erosion, but the soils in the Blue Mountain 
range area derived from schists are easily erodibie, whilst uncontrolled 
deforestation has been permitted to proceed too far in the island. 

In St. Vincent, soil erosion can be really serious, and one or two small- 
holding settlement schemes have, in the Cumberland Valley of that island, been 
established on lands situate on hill slopes which slioujd have been kept in 
permanent forest cover. The condition ot these small-holders, after some years 
on land of inferiors quality subject to continued erosion can well be imagined, 
and it is to be hoped that in all future settlement schemes attention will be given 
to the selection of land of good average quality, and that no scheme be started 
until a satisfactory report on the land has been obtained from the Department 
of Agriculture. In St. Lucia, attention has recently been called by Mr. 
Wimbush, in his report on the forestry position in the Windward and Leeward 
Islands, to the unsuitability from the stand-point of erodibility of certain 
lands recently selected for development, and a re-consideration of the project 
has resulted in a revision of the proposals. 

In Trinidad, the Imperial College of Tropical Agriculture is studying the 
amount of erosion on certain soil types in connexion with investigations relating 
to shifting cultivation. 

More attention should, however, bo directed to the question of soil erosion 
in all the wetter and more mountainous islands in the West Indies, and all 
Colonial Agricultural Scholars should, whilst at the Imperial College of Tropical 
Agriculture, have their attention specially directed to the question. 

General Conclusions. 

An attempt has been made to survey the present position in regard to 
soil erosion in the Colonial Empire, to describe the measures which are being 
taken to check and control its effects and to indicate where further efforts are 
required. 

The most serious losses are taking place in East Africa, particularly in 
Kenya. Here the condition of some of the Native Reserves is becoming serious 
and deterioration is proceeding apace* It is the most important land problem 
which the country has to face, but if active steps are taken without delay the 



NOTES. 


61 


position can be greatly improved within a decade. The actual causes of erosion 
are numerous and varied, and each drainage area of any country requires close 
examination before plans of reconditioning or control are decided upon. 
Untutored agricultural operations are responsible for erosion in many parts, 
whilst in others concentrations cf stock numbers due to a shortage of grazing 
or inadequate water supplies are the chief contributory causes. In yet others, 
stock numbers are in excess of the carrying capacity of the land and overgrazing 
takes place. Rotational or deferred grazing has been demonstrated to be 
effective as a cure in certain circumstances, and strip-cropping, contour-ridging, 
and mulching have proved their value in agricultural lands. There are many 
instances where deforestation has been excessive, and considerable areas of land 
may have to be retired from cultivation or grazing if the position is to be 
improved. 

The problem is one which must be approached from various angles. Physical, 
biological and social factors have to be considered, and there is no doubt that the 
fullest co-operation between the administrative and technical departments is 
essential if advances are to be made. Generalizations as to control measures 
must be avoided. Each area should be examined in detail and working plans 
evolved before any decision is taken as to how the problem should be tackled. 

Vegetation-control is the most important method of controlling soil erosion, 
since it produces a cure by natural methods and is much less expensive than 
treatment by mechanical means. In cultivated lands on hilly slopes, however, 
the use of contour-ridges, tei races, hedges and drains is necessary when strip- 
cropping cannot be adopted, if the tortile top soil is to be saved. 

The uso of control measures, without an improvement in the systems of 
agriculture and animal husbandry, is likely to be unsatisfactory. Buck a policy 
meets only the circumstances of the present and does not provide for the future. 
Expenditure on anti-erosion measures should at least be matched with expendi- 
ture of a similar magnitude for agricultuial education, demonstration and 
propaganda, it the future is to be secured. 

Clarification of Sugar Syrups.— -In the December 18, 1937 number of Chem- 
istry and Industry, A. Nagaraja Ran and B. B. Gupta published the following 
letter on this subject : — 

Considerable difficultly is being experienced in the preparation ot cOftcen- 
trated, clear and brilliant syrups from most of the sugars manufactured in India. 
Repeated treatment with large amounts oi activated carbons, followed by more 
than one filtration, has boen found to solve the problem partially. It is, 
however, still believed that the syrups made from imported sugars are far more 
satisfactory. # 

The manufacture of concentrated, clear and colourless sugar syrups is of 
great industrial importance and the utilization of Indian sugars (even the lower 
grades) for this purpose has been investigated in this laboratory for some^ time. 
We are glad to report that a new method developed by us has been found to be 
very satisfactory. 



AGRICULTURAL JOURNAL OF BRITISH GUIANA, 


62 


[IX, t 


The syfu p is treated with jtwt the minimum quantity of sodium alumin&te 
and activated carbon and then a current of carbon dioxide is passed through it to 
saturation. After allowing the mixture to stand for some time (about 15 
minutes), the mixture of aluminium hydroxide and active carbon is removed by 
filtration to obtain a satisfactory syrup. It would not be out of place to mention 
here that the application of similar methods is being tried by us, also for the 
clarification of the different products in the various stages of the sugar industry, 

Aluminium hydroxide has already been employed before for similar 
purposes by others, but there is always a definite advantage gained^iu the 
method indicated above over the others, in that here the amount of aluminium 
left over iu the filtrate (syrup) has been reduced to the minimum. Besides, in 
this method the active aluminium hydroxide is generated in situ and well 
mixed up with the active carbon thereby enhancing its decolorization property 
also. 


Legislation* — The following have been appointed Inspectors in the terms of 
Section 19 of the Plant Diseases and Pests (Prevention) Ordinance, 1935 : — 

The Director of Agriculture 

The Deputy Director of Agriculture ' 

The Entomologist 

The Botanist and Plant Pathologist 

All Agricultural Superintendents, Assistant Agricultural Superintend- 
ents and Agricultural Instructors. 

Technical Assistants to the Entomologist and Botanist. 


An Ordinance to provide for the control of Sugar Experiment Stations for 
a period of five years from the first of January, 1938, has recently been passed. 


In accordance with Section 3(1) and (3) of the Animals Diseases Ordinance, 
1936, the following list of Registered Veterinary Surgeons was recently 
published for general information. 


Name 


Date of 
Registration 


Address. 


Benjamin, Charles Bishop 
Bruce, Samuel Nathaniel, D V M 
Fraser, Hugh Arthiu, B V.Sc, 

Fulton, Andiew MePheison, D.V H., 
M,R C. V.S. 

Hanaro i, James 

Kerry, Robert Retna 

Khan, Eli Raksh ... r 

Larrouv, Francis Isaaore 

Mitchell, Henrv Alfred 

Bone, Thomas, O.B.E., M.R (\V S 


27.10. am 
16. 4.1020 
12. 9 1933 


Plaisance, E C„ Domerara 
127, Laluni Street, Georgetown. 

5, David Street, Kitty, E.C., Demerara. 


5, 7.1924 
27.lO.UKKi 
27.10.1909 
27 10.1909 
26.* 5.1909 
20. 8.1909 
19 91928 


Vryheid’s Lust, E.C., Demerara. 

Agricola Village, E.B., Demerara 
Peter’s Hall, E.B., Demerara. 

Public Hospital, Georgetown. 

Messrs. Brodie & Rainer, Georgetown. 

31, Camp Street, Georgetown. 
Department of Agriculture, Georgetown, 

JA * — 



REVIEW. 


The Practical Atpeeh of Copra Deterioration : by F. C. Cooke. Bulletin No. 

28, General Series, Department of Agriculture, Kuala Lumpur, F.M.S. 49 

pp. Price 50c. 

The author is to be congratulated on a bulletin which should be of 
the greatest value to copra producers. Like good copra, it is clear and com- 
pact, free from the excess moisture of verbosity and the disfiguring mould of 
unnecessary technicality. Although the basis of the work is essentially chemi- 
cal, only the practical applications and arguments are shown, and these make 
straightforward reading. Any attempt to summarize the bulletin would be 
futile, since it is in itself a summary, and its range can be seen from the section 
headings given below. 

Part 1. bitrodintion : moisture content and quality : the range of quality : 
the marketing of copra • conclusions. 

Part II. Copra Deterioration : review of previous literature : the charac- 
teristics of deterioration : agents ot deterioration : deterioration due to moistuie : 
deterioration due to smoke and heat : the production of ’* smalls ”, fractures and 
dust : variations in the oil content 

Part III. The Pi event am ol Deterioration : analysis of the causes of 
deterioration : the prevention of deterioration — pre-treatment of nuts, copra 
drying, after-treatment of copra. 

* 

Part IV. Copra Griuhni/ field and laboratory grading : commercial 
grading. 

Not a word is wasted, and for that reason it requires- careful study, but the 
time and effort will be well spent. 


D.W.D. 



MINUTES OF THE FIFTEENTH MEETING OF THE BRITISH 
GUIANA BEEKEEPERS’ ASSOCIATION HELD AT THE 
HEAD OFFICE, DEPARTMENT OF AGRICULTURE, 
GEORGETOWN, ON MONDAY, JANUARY 24. 

PRESENT. 

Mr. E. A. Borman, .... President (in tho chair) 

Prof. J. S. Dash (Director of Agriculture), 

Messrs. E. S. Vieira, C. A. Quail, M. P. Correia, 

D. M. Khan, Robert Williams. E. S. Christiani, Jr., 

D A. Iloo, W. M. A.Roberts, M. J. Henriques, , _ 

.7. G. Martin, 0. C. Dowding, K. W. Ferdinand, H. "" Member*. 

Cliand, H. Madramootoo, G. W. Roberts, N. A. 

Rickford, A. Hn-a-Kam, Mrs. I. Tjon-a-Man and 
Miss H. L. Ferdinand 

' with 

Mr. H. D. Huggins .... Secretary. 

Excuses for their absence were received from Messrs. J. W. Perry, J, C* 
DaSilva, J. A. Trotinan, Mohamed Ishak, W. Humphreys, D. A. Pile, K.C. Hose, 
P. A. Iloo and S. A. King. 

Minutes. 

The Minutes of the previous meeting held on Monday, July 2fi, 1037, were 
read, and on a motion by Mr. C. A, Quail, seconded by Mr. E. S. Vieira, were 
confirmed. 

Fixing . the price op Honey. 

Referring to the minutes, Mr. Henriques asked what action was being 
taken in regard to the fixing of honey prices. The general opinion was that 
the most expedient step was to appoint a standing committee, as the Director of 
Agriculture had i>reviously suggested, to report on what action should be taken 
from time to time. After some discussion it was agreed that the President, the 
three Vice-Presidents with Mr. Henriques and Mr. Huggins be appointed to form 
the Committee. 

Election of Office-bearers. 

On a motion moved by Mr. Henriques and seconded by Mr. J. G. Martin, 
the following members were elected to the Executive Committee for 1938 : — 

His Excellency the Governor .... Patron 

Mr. E. A. Borman .... .... President 



MINUTES OF THE B. O. BEEKEKPEBS’ ASSOCIATION. 


65 


Mr. W. M. A. Roberts 
Mr. C. A. Quail 
Mr. 8. A. King 
Mr. R. B. Hunter | 

Mr. D. A. Iloo l 
Mr. A. M. Fulton J 
Director of Agriculture 
Mr. H. D. Huggins .... 


Vice-President 

Vice-President 

Vfcco-President 

Members of Committee 

Ex-oilicio Member 
Secretary -Treasurer 


On behalf of those elected the President thanked the members and gave 
the assurance that an ettort would be made to maintain the useful services of 
the Association during the year that was ahead. 


llm Excellency the Governor to be asked to be Patron. 

It was decided that His Excellency the Governor, Sir Wilfrid Jackson, 
K.C.M.G., should bo asked to become Patron of the Association, which honour 
his predecessors had been pleased to confer on the Association. 

Secretary’s Report. 

The Secretary's Report was then read. 

Referring to the report, Mr. Ilenriques suggested that more advertising 
should be undertaken. 

The Director of Agriculture drew attention to the considerable variation in 
honey crops. He pointed out that both consumption and production had gone 
up and that, ii beekeepers wanted to be assured that production would at all 
times keep pace with demand, the supply of nectar plants should be increased. 
He was pleased to see lady members present and he hoped the indication was that 
interest in the movement was spreading. He was of opinion that \illage 
organisations might, with advantage, make beekeeping discussions with practical 
demonstration one of the phases of their activities. He mentioned that although 
the demand was not great there were at intervals enquiries for section honey. 

Mr. D. A. Iloo drew attention to the fact that the Department had en- 
couraged the distribution of honey plants by ottering special prizes. 

Mr. Dowdiug reminded members that the value of bees could not be 
estimated only from honey sales but the great service they did in regard to 
pollination and setting of fruit was important. 

Mr. Borman mentioned that the village movement idea was an excellent 
one aud he wab already playing his part, since, on more than one occasion, he 
had given short talks to village organisations. 

The Director of Agriculture suggested that a permanent advertising dis- 
play, say in a grocery, was worth considering. 

Mr. Iloo moved the adoption of the report and Mr. Vieira seconded* 



66 ■ ' AGRICULTURAL JOURNAL OF BRITISH GUIANA. [ISC, t 

Honey Display at the Berbice County Agricultural Exhibition. 

The next item considered was the exhibition to be held in Berbice. After 
some discussion it was agreed that the Executive Committee should meet to 
discuss the space available and type of exhibit to be prepared for display at the 
forthcoming County Agricultural Exhibition to be held in Berbice. 

The Director of Agriculture suggested that it might be -arranged at some 
future meeting to have one or two papers presented by some of the more 
experienced beekeepers. Mr, Iloo agreed that this would be a good idea and was 
of opinion that his brother Mr. F. A. Iloo, would be willing to contribute one. 
Other names suggested were Mr. E. A. Borman, Mr. K. B. Hunter, Mr. L. D. 
Cleare and Mr. H. W. B. Moore. 

The view was also expressed that it would be a pity if at ordinary meetings 
members, especially younger members, should refrain from expressing their 
opinions on subjects raised for discussion. 

More than one member stated that beekeepers on the whole would be glad 
if it were possible for more beekeeping extension work to be done by the 
Department of Agriculture. There were many beginners for whom helpful 
attention was desirable. 

Mr. Henriques suggested that the Association might approach (Government 
with the object of obtaining a loan for the purpose of establishing the industry 
on a more extensive basis. 

In regard to extension work, the Director ot Agriculture mentioned that 
during the week of the County Agricultural Exhibition, Mr. Huggins would be 
in Berbice and it could probably be arranged for him to discuss their difficulties 
with the Berbice beekeepers. 

The President read his report. He was thanked for his excellent summary 
of the year’s activities and achievements, arid the Director of Agriculture 
moved that the report be placed on reoord. Mr. C. A. Quail seconded. 

Appreciation was expressed by the President and others for the interest 
taken by Mr. R. Williams of Rosehall, Corentyne, Berbice, and Mr. D. M. Khan 
of West Coast, Berbice, in being present that afternoon. 

At this Stage Mr. Henriques proposed Messrs. Z. D’ Andrade and L. 0. 
fcimith as members. 

The Chairman then thanked members for attending and the meeting 
to. a close. 



NEWS 


A meeting of the Board of AgrionUnre was held on January 4 mainly 
to discuss the plaintain export trade and the Cattle Branding Ordinance. 

The British Quiana Beekeepers’ Association held its Annual General 
Meeting on January 24. Minutes of this meeting are published elsewhere in 
this Journal. 


The Director and the Deputy Director, accompanied by the Agricultural 
Superintendent of the District, visited the experimental banana plot at Middlesex 
and the Toevlugt Farm Unit on January 1 3. The Deputy Director visited these 
trials on several occasions during the period under review. The Plant Patho- 
logist visited the banana plot on January 11 and began spraying operations with 
Bordeaux mixture as a control against Leaf Spot and Panama Diseases. 

The Deputy Director also visited Esseqnibo: East Coast, Demerara and 
Berbice. 


The Director of Agriculture and the Hon. C R. Jacob left the Colony on 
January 20 for Surinam on a special mission to make a study of the situation in 
regard to the coffee industry and the recently organised Surinam Central Coffee 
Board. 

On the Director’s return on February 5 he proceeded to Trinidad to 
represent British Guiana at the Conference of the British West Indian Fruit and 
.Vegetable Council held from February 9 to 15. During the Director’s absence 
Capt. F. Burnett. Deputy Director, was appointed to act. 

Mr. 0. C Dowding, Agricultural Instructor, resumed duty after leave of 
absence on December 8. 

The Secretary of State for the Colonies has been pleased to approve of -the 
appointment of Mr. C. H. B. Williams, M.A., A.I.C.T.A., Dip. Agr., Cane 
Agronomist, to the post of Sugar Agronomist and Plant Breeder as from 
January 1, 1938. 

Consequent on the appointment of Mr. E. M. Morgan as Assistant Agricul- 
tural Superintendent, Mr. H. A. Cole, Agricultural Instructor, has been promoted 
to the Senior Grade. 


Mr. I. Dewar has been appointed to act as an Agricultural Instructorfrom 
February 1, 



•68 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 1. 

A Conference of the District Staff and Headquarters Officers concerned 
was held on January 20 and 21 and was presided over by the Deputy Director ; 
the various programmes of district work and experiments to be carried oat 
during 1038 were discussed. 


Livestock importations by the Department during recent months have 
included: 

Cattle. (Immunised against tick-borne diseases) 

5 bulls and 3 heifers (Red Poll) 

2 bulls and 3 heifers (Hereford) 

Pigs. 

2 gilts and 1 boar (Canadian Berkshire) 

Poultry. 

2 cockerels and 8 pullets (Barred Rocks) 


Among recent visitors to the Department were the Hon. E. J. Waddington, 
C.M.G., Colonial Secretary ; Prof. F. Hardy and Messrs. B. N. Ray and 0. F. 
Churaman, from the Imperial College of Tropical Agriculture: Mr, J. J, Ochse. 
from Surinam; Monsieur Montayne, Dutch Consul General in New York; Mr. A. 
Wanford, of the Employers’ Liability Assurance Corporation, Ltd., London ; 
Mr. W. D. Lambie, His Majesty’s Trade Commissioner for the West Indies ; 
Mr. M. B. Palmer, Canadian Government Trade Commissioner and Mr. 
Edward J. King, M.C., Secretary of the British Empire Producers’ Organization. 


His Majesty the King has been pleased to appoint the Honourable E. .T. 
Waddington, C.M.G., to be Governor of Barbados. Mr. Waddington, who was 
Colonial Secretary of this Colony since September 20, 1113.'), has always evinced 
the keenest interest in matters connected with the agricultural progress of the 
Colony. 

As we go to press, news has been received that the Hon. G. D.Owen.C.M.G., 
Colonial Secretary of Barbados, has been appointed Colonial Secretary of British 
Guiana vice Mr. Waddington. Mr. Owen has formerly served in British Guiana 
from February 13, 1925 to September 3. 1931. 



PLANT AND SEED IMPORTATION. 

Introdaotions by the Department of Agriculture for the period 
November, 1937— February, 1938. 


Name 

Quantity. 

Whence Supplied 

Economic. 



Derria fUiptiea 

cuttings 

Puerto Rico Agrl. Expt. Stn., 
Mayaguez, Puerto Rico. 

Tepkroftiu toxica via 

seed 

do. 

Cracca ( Tephrosia ) cogel Hi 

seed 

do. 

Tree Tomato— Ct/phomandra hetacea 

1 ox 

East African Agrl. Research 
Stn., Amani, Tanganyika. 

Tobacco Seed— Gold Dollar Strain 8 

2 oz. 

Coker Pedigreed Seed Co, 
Hartfiville. S.C. 

Lentils— Types 11 and 47, Hybrid | 
111-86. 

1 oz each 

Botanical Sub Station, Imp. 
Dept of Agriculture iu In- 
dia. Puna. 

Peas— S. 21) and A-15 

do. 

do. 

Assorted Vegetable Seeds 

I 

20 lb 

Messrs. P. Henderson & Co., 
New York. 

Ornamental , 


1 

i 

Flovvei SeedH— Assorted ( 

182 pkts. 

| do 

Poses— Double White Killarney 

2 plants 

j do. 

Hoses ,0 varieties 

8 plants 

1 

Messrs. H. G. Hastings, U.S.A. 

Poses 10 varieties 

24 plants 

Messrs. Benjamin R. Cant & 
Sons, Colchester. England. 

A macaw t ere/ ho 

1 plant 

Messrs, G. Reuthe, Ltd., 
Keston, Kent, England 

Lonicera Uddeln and i ana 

1 plant 

do. 

I 

Thnt/a oriental is 1 

1 plant 

do. 

i 

DendrocaUumi* ^ti ictus 

i 

2 plants 

Puerto Rico Agrl. Expt. Stn.. 
Mayaguez, Puerto nioo. 

Ha i a m out i a grandi ft ora 1 

2 plants 

do. 

(tlirt/cidiasejnum 

10 cuttings 

do. 

Phaeomn ia * periom j 

1 plant | 

do. 

Vanilla plan if cilia 

2 cuttings J 

do. 



METEOROLOGICAL DATA, 1937. 

BOTANIC GARDENS, GEORGETOWN. 


1937 

Months 

Rainfall, 

Inches 


Number of Days of 

Bain 


Evapora* 

tion, 

Inches 

Under ! 
.10 in. j 

f .10 in. 
to 

.50 in. 

.50 in. 
to 

1.00 in. 

A « 

*-» Ol 

Above 
2.00 in. 

Total 

Days 

Janaary 

11.41 

5 

8 

2 

1 2 

2 

19 

4.01 

February 

.95 

9 

2 




11 

5.08 

March 

1.26 

9 

6 



... 

15 

5.88 

April 

5.44 

3 

10 

1 1 

1 

... 

15 

5.51 

May 

12.43 

4 

10 

8 j 

4 

... 

26 

1 4.23 

Jane 

17.80 

7 

9 

5 

6 

i 

28 

3.76 

July 

15.63 

3 

12 

5 

2 

i 2 

24 

3.88 

August 

7.22 

3 

12 

3 

1 

j 

• M 

19 

4.60 

September 

3.16 

3 

3 

• . ■ 

1 

1 

7 

5.69 

October 

3.10 

1 

5 

1 

1 

• • ■ 

8 

5.44 

November 

4.10 

1 1 

4 

3 

i 1 

... 

9 

4.76 

December 

9.66 

6 ! 

! 6 

3 

l 3 

1 

18 

3.12 

Totals 

| 92.16 

54 

1 

j 87 

1 

31 

1 20 

'7 

199 

55.96 


AIR TEMPERATURE AND HUMIDITY IN THE SHADE. 

BOTANIC GARDENS, GEORGETOWN. 



Air Temperature 1 

Hnmidity 

Mean 

Months 

Maximum 

Minimum 

Mean 

January 

83.6 

76.0 

79.8 

84.7 

February 

84.5 

75.7 

80.1 

77.9 

March 

85.0 

76.5 

80.7 

77.2 

April 

85.5 

76 3 

80.9 

78.8 

May 

84.5 

76.9 

80.7 

83.9 

June 

84.9 

75.6 

80.2 

85.7 

July 

84.8 

1 75.1 

79.9 

84.7 

August 

86.1 

75.8 

80.9 

83.5 

September 

88.2 

76.4 

82.3 

79.8 

October 

88.9 

76.5 

82.7 

79.G 

November 

84.3 

76.7 

80.5 

81.5 

December 

86.1 

i 

76.2 

81.1 

82.2 

Mean 

85.5 

76.1 

80.8 

81.6 








WETTEST AND HOTTEST DAYS AT VARIOUS STATIONS. 


Stations 

Wettest 

Days 

Rainfall, 

Inches 

t 

Hottest 

Days 

Temper- 

ature 

in shade °F 

Botanic Oardens, 
Georgetown 

j 

^ June 19th 

3.14 

1 

1 

Sept. 9th 

92.5 

New Amsterdam, 
Public Gardens 

July 2.nh 

3.48 

Sept. 8th & 
Oct. 23rd 

1 

j 94.0 

Ouderneeming Indus- 
trial School, Essequibo 

Jan. 6th 

3.60 

Dec. 8th 

93.0 

Hosororo, 

N.W.D. 

Dec. 24 th 

~ - I 

3.38 

i 

Sept. 9th 

! 

i 94.0 






CURRENT PRICES OF COLONIAL PRODUCE 


From The Commercial Review , Journal of the Georgetown Chamber 
of Commerce , Vol. XXL ', No, 2 , Tuesday, 28th February, 1938. 

SUGAR. 

Per 100 lb. net 3 lb. per Bag allowed for tare 


Dark Crystals for Local Consumption $3.30 

Yellow Crystals do. do $4.00 

White Crystals $4.75 

Molasses Sugar none offering. 


Above Prices include Excise Tax of 90c. 

RUM. 

Imperial Gallon. CaBk included. 

Coloured, in Puncheons — 40 to 42 O.P...(for export). ..60c.; Hhds. 52c„ Barrels 77c 


White, in Hogsheads— 40 to 45 O.P...(for local consumption) 45 to 55c 

MOLASSES. 

i 

Per Imperial Gallon. Naked. 

Yellow (firsts) 10c. 

Yellow (seconds)...! 5^c. 


RICE. 

Rice per Bag of 130 lb. gross. Brown Super $3.30 to $4.00 ; No. 1, $3.60 — 

$3.75 ; White, None available. Lower Grades $2.75 — $3.00 as to quality 
Padi per Bag of 143 lb. gross, $1.00 to $1.50 as to quality. 


GENERAL. 

Gold, Raw average per oz. $26 to $27. 

Diamonds, — pro rata as to quality average per carat $10 to $11. 

Timber, Greenheart, (Lower grade measurements). ..40c. to 60c. per c. ft. ; 

for export 72c. to $1.00 perc. ft. 

do. Railroad Sleepers — (Mora) $1.68 each. 

Greenheart Lumber $70 to $80 per 1,000 feet. 

Crab wood Lumber $60 to $75 per 1,000 feet. 

Shingles, Wallaba, 4 x 20 and 5 x 22 inches $4.50 to $6.00 per M. 

Charcoal, Capped for shipment 72c. to 85c. per bag. 

Firewood $2.50 per ton. 

Coconuts... Selects, $9.00, culls $6.00 per M... Copra $1.75 per 100 lb. prime Copra, 

Balata Venezuelan, none. Local Sheet.. .36c. to 38c. per lb. 

Cocoa 19c. to 19ic. „ „ 

Coffee ! 5c. to 5jc. „ ,, 


N.B.— Duty Payable on value at time of Importation and rate of exchange on day of 
arrival. 



Vol. IX, No. a. 


June, 1938. 


The 

Agricultural Journal 

of 

British Guiana 



I5S03 

PUBLISrfCD BY 


THE DEPARTMENT OF AGRICULTURE, 

GEORGETOWN. BRITISH GUIANA 


Price 


• ■ 
• 1 


•» 


• a 
M 


. 6d. 




DEPARTMENT OF AGRICULTURE. 


ADMINISTRATION 

Director of Agriculture 
Deputy Director 

Clerical 


Senior Clerk 
Registrar of Banks 

Class III Clerks 


Probationers 


Librarian 

RESEARCH BRANCH. 

Botany and Plant Pathology 

Botanist-Plant Pathologist and Superintend - 
ent. Botanic Gardens : 

E. B. Martyn f B A., AXC.T.A. 

Technical Assistant : 

N. Persaud 

Chemistry 

Chemist : 

D, W. Dufchie, M,A , B.Sc., Ph.D , FXC, 
Assistant Chemist : 

C. L. C. Bourne 

Entomology 

Entomologist : 

L. D. Clear©, F.R. Ent. 8. (ou leave) 
Technical Assistant : 

C. Williams 

Rico 

Assistant Plant Breeder : 

P. A. Chan-Choong, B.Sc , A.I.C T.A. 

Sugar 

(In co-operation with the Sugar Producers) 
Sugar Agronomist and Plant Breed* r : 

C. H. B. Williams, M.A., A.I.C.T.A., Dip. 
Agr. (on leave) 

Laboratory Assistants ; 

H. B. Singh 

A, V. Wan-Ping, Dip. Agr, 

Statistical Clerk ; 

J. B. Bourne 


Prof. The Hon. J. Sydney Dash, 

B.Sc. (Agnc.) 

... F. Burnett, M.C., M.A, 

Staff. 

... J. F. Irving, M.C. 

W. G. Delph 
( A. A. Thorne 
] Miss N. Green 
( Miss D, M. Terrill 
Miss M. Cheong 
P. 0. Jackson 
S. A. Adams 
Miss B. Delph 

Miss V. Ohan-Choong (on leave) 

LIVESTOCK BRANCH 

Veterinary Surgeon : 

T. Bone, O.B.E., M.B.C.Y.S. (on leave) 

H A Fraser, B.V. Sc. (acting) 

FIELD BRANCH 

Agricultural Superintendents: 

Berbice— J. D. Gillespie, B.Sc. 

Demerara, East— E. M. Peterkin 
Demorara, East Bank — H. D. Huggins, 
M.Sc., Dip. Agr. 

Demerara, West— E. G. Benson, B.Sc . 

A.I.C.T.A., Dip. Agr. 
Essequibo-A. A. Abraham 
Assistant Agricultural Superintendent : 

Berbice— E. M. Morgan 
Agricultural Instructors : 

Botanic Gardens — H. A. Cole 

fC C. Dowdmg, F.L.S., 
Demerara, East—] F.B.H.S. 

IW. A. Bo veil. 

Demorai a. East Bank— I. Dewar (acting) 
Essequibo— A. W. Sears 
NorthWest District— L. E. McKinnon 
Agricultural Assistants: 

Demerara, East — J. Indrobeharry 
Berbice— H. B. France 

Sugar 

Field Manager (Central Station) 

C. Cameron 
Field Assistants x 
L. A. Forte 
B. A. McArthur 



METEOROLOGICAL BRANCH 

Technical Assistant : 

D. D, Blackman 

Meteorological Assistant'. 

J. E. Isaacs 


RICE GRADING BRANCH 

Grading Inspector : 

H, E. H. Gadd (on leave) 

H. D. Huggins (acting) 

Technical Assistants : 

G. L, Leitoh 
R. R. Ross 


ADVISORY BOARD OP AGRICULTURE 

Director of Agriculture, Chairman, ex officio . 

Deputy Director of Agriculture, Vice-Chairman, ex officio. 


Hon. Peer Bacchus 

Hon. R- E. Brassington 

Hon. J. W. Jackson 

... 

... 

\ 

► Members 

Hon. F. J. Seaf ord, o.n.F 

Mr. S. Andries 
„ R. B. Hunter 

... 



„ W. H. Richards 

... 


/ 



SUGAR EXPERIMENT STATIONS COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 

Hon. M. B G. Austin, o.n.r.. 

Mr. H. F. Chapman (acting for Mr G. M. Ecclos) . 
„ J. C. Gibson 
„ A. Murison 
„ R. E. Rhodes 

„ J. Sutherland (acting for Mr. J. Bee) 


Georgetown 
Pin. Bath 
Pin, Port Mourant 
Pin. Uitvlugt 
Pin. Diamond 
Pln. f ()gle 


CO-OPERATIVE CREDIT BANKS’ BOARD. 


Director of Agriculture, Chairman, ex-offieio. 
Dr. the Hon. J. B. Singh 
Rev. A. E. Dyett ... 

Mr. C. Farnum ... 

„ J. L. Wills .. 




Members 


Representing 
the Sugar 
Industry 
which main- 
tains the 
Stations 


DISTRICT AGRICULTURAL COMMITTEES 


EAST DEMERARA 

Director of Agriculture, Chairman 
District Commissioner 
Doputy Director of Agriculture 
Hon. J. I. de Aguiar 
Hon. E. M. Walcott 
Mr. S. Andries ... 

„ M. Ghani 
„ W. H. Richards 
„ J.E. Wills ... 



Members 


Director of Agriculture, Chairman 
District Commissioner 
Deputy Director of Agriculture 
Hon. J. W Jackson 
Dr. the Hon. J. B. Singh ... 

Mr. R. P. Carryl ... 

„ J. C. DaSilva 
„ R. B. Hunter * ... 

A. Murison ... 

,, W. Ramdeholl 

,, A. Rayman ... ... 


WEST DEMERARA 


P 


Members 



CONTENTS. 



(Vol. IX, No. 2.) 

PAGri 

EDITORIAL — The Rice Situation .. 

73 

ORIGINAL ARTICLES. 


Malaria in British Guiana, 
Parti. 

... G. Giglioli. M.D. (1/.), M li.C.P. 
D.T.M. & II. {Eng.) ... 

(Land.), 

73 

Results of Padi Varietal Trials 
and Extension Work, 1937 

... F. Burnett, <I.C., M A. ... 

K2 

The Variety and Fertiliser 
Position of the Sugar 
Industry, IV. 

... Holman B. Williams. M.A., 

A.I.C.T.A.. Dip. Agr. 

101 

SELECTED ARTICLE. 


Edible Coconut Oil 

... Reginald Child, F.I.C., B.Sc., 
Ph.D. ( Lund .). 

109 


NOTES. 


Boron in Agriculture 

*'< ... |,| 

117 

New Ornamental Plants 
in the Botanic Gardens 


119 

Legislation ... 


... , 120 

British West IndieB Fruit and 
Vegetable Councils 

* • * «»l n, 

120 

NEWS 

••• ••• • ft « 

120 

PLANT AND SEED IMPORTATION 

129 

METEOROLOGICAL DATA 

••• itt 

130 

CURRENT PRICES OF COLONIAL PRODUCE 

131 



Contents — Continued. 

ILLUSTRATIONS 


Pacing Page 


Plate 

I.— Fig. 

1 — Anopheles alhitarsis: Adult Female, 

76 


,,-Fig. 

2— Wing markings of (a) A. alhitarsis; 

(b ) A. darling i. 

... 76 

Plate 

II.-— Fig. 

3— Caudal portion of the larva of A , darlingi. 

78 


,,-Fig. 

4 — Papa? of (a) .4. alhitarsis; (b & c) 

A. darlingi. 

78 

Plate 

III.— Fig. 

5— Breathing Trumpets of A, alhitarsis. 

80 

M 

„ —Fig. 

6— Breathing Trumpets of .4 . darlingi. 

80 

Plate 

IV.— Fig. 

1— Relative Varietal Composition of the Cane 
Areas to be harvested in British Guiana 
in 1938. ... 

... 102 

Plate 

V.-Fig. 

2— Relative Quantities and Values of Fertil- 
isers used on British Guiana Sugar 
Estates, in 1937. 

107 



Guiana. 


The 

Agricultural Journal of British 

June, 1938. 

EDITORIAL 

THE RICE SITUATION. 


Rice is the second most important agricultural industry of this Country, 
The frequent standard of estimating the importance of the crop in relation to 
the other industries is the value of exports. This may lead to an underestima- 
tion of tho worth of this crop since rice is the most important article in local 
diet ; consumption is increasing, the figure at present being approximately 
24,000 tons annually, compared with an average export of 111,000 tons during 
the last five years. These figures furnish a better means of appreciating the 
crop’s real importance. 

As rice is grown almost entirely by the small producer, the vicissitudes of 
its production and marketing affect a considerable part of the Colony’s farming 
population. 

In agriculture, as in other walks of life, a proverb often quoted is : “ Man 
proposes, God disposes/’ Man has made many proposals for the betterment 
of the rice industry in recent years, but the latter half of the pro\erb has been 
too much for him. For a number of years, up to 1933, rice production expanded 
remarkably but early in 1934 there came a flood whose damage was only loss 
than the ill-effects of the drought which followed and lasted for the rest <rt the 
year ; the Colony’s rice exports were halved. 

In 1935-36, production was again low on account of unfavourable weather 
conditions. Further, rice prices declined steadily: for example, the average 
price per 1 80 lb. bag of 44 super” grade was $4.02 in 1934, $3.83 in 1935 and 
$3.39 in 1936. 1 Rice is a relatively short-term crop (compared, for instance, with 
sugar) and the area under cultivation from crop to crop reacts sensitively to price 
changes. Hence, although prices rose in 1937 — super rose to $3.85 per bag — 
production, while taking an upward turn, was still below the high level 
reached a f$w years previously. 



74 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [IX, 2, 

The Fear 1938 broke with prospects for the rice producer distinctly 
promising i a fair crop had been harvested and prices for forward shipments 
were higher than they had been since 1934. Unfortunately, the first half of 
1938 has been characterized by rains more continuous and more abnormal than 
those of any year for which records are kept — the year 1893 alono excepted. 
The effect has been to render milling difficult and in some instances to bring it 
to a standstill. Almost all cf the rice produced in British Guiana is parboiled. 
Padi is soaked in water, steamed and then dried on concrete floors in the sun. 
If the interval between steaming and drying is unduly long, rice of poor quality 
results. It is at this stage — the drying stage — that milling operations have 
broken down within recent mouths, since intermittent showers have made it 
well-nigh impossible to obtain sufficient sun to dry padi thoroughly enough for 
milling. The significant result of this season’s experiences has been the fixing 
of attention on the great necessity for improved drying facilities in the Colony’s 
rice factory organisation. It is universally admitted that had factory equipment 
included mechanical driers not only would good quality rice have been available 
but the Caribbean markets would have absorbed a much larger part of our crop 
at an attractive price before Burmese shipments began to arrive in April-May. 
A feature of recent years has been the improvement in quality of padi through 
the more general use by farmers of pure line seed distributed by the Department 
of Agriculture ; it is unfortunate that the advantages of this improvement aro 
not fully enjojed by growers on account of poor milling facilities. Out 
of evil m^y ' yet come good, it this season’s misfortunes have 
succeeded in demonstrating the necessity for improved rice factory 
equipment in general and in drying facilities in particular. 

In regard to the Market outlook it is not easy to make a forecast for the 
latter part of 1938. The area sown in Burma in 1937-38 was the largest since 
1933-34. Tndia is the leading importing country but production this season is, 
with one exception, the largest since 1931-3*2. On the whole, therefore, imports 
into India from Burma are likely to be relatively small. It is not possible to 
gauge accurately what will be the imports into China since tho far eastern hos- 
tilities must assuredly have far-reaching effects on the rice growing and consum- 
ing areas. Production in the Japanese Empire has this year attained a record 
and is in excess of the population’s requirements ; in addition, stocks at the 
beginning of the season were large. Imports are therefore not likely to be drawn 
upon. In British Malaya, relatively low rainfall led to expectations of a short 
crop but the setback in the rubber situation is considered likely to affect rice 
imports. The situation in Ceylon indicates that no great change is likely to take 
place in regard to imports. Production in Java has been rising in recent years 
so that not only have domestic supplies been met but exports have actually been 
made to the Outer Provinces. These circumstances indicate that Burmese ship- 
pers are likely to take steps to dispose of as much of their present crop in the 
Caribbean as that market can be induced to absorb, 



ORIGINAL ARTICLES. 


MALARIA IN BRITISH GUIANA, 


PART I. THE ANOPIIELINE MOSQUITOES OF THE COLONY, 

BV 

G. GIGLIOLI, m.d. (It,), m.r.c.p., (Loud.); d.t m. & h. (Eng.). 
Medical Adviser to the Sugar Estates of British Guiana. 


The malaria problem, in all its phases, is intimately related to agriculture : 
malaria is eminently a rural disease and rural and agricultural populations suffer 
most from its ravages 

Malaria is closely connected with the distribution of surface waters and 
land configuration ; agriculture, by altering surface water conditions and land 
configuration, through drainage and irrigation, directly affects, beneficially 
or adversely, the incidence of malaria. Extensive agriculture often favours 
malaria ; intensive agriculture, on the contrary, radically eliminates it. It 
is by the forcible establishment of intensive agriculture in localities recently 
reclaimed by drainage, where malaria had reigned supreme for ages, that such 
brilliant results have been reaped, in less than a decade, in the Pontine marshes 
and other classical malaria regions of central and southern Italy. 

Agriculture, in this Colony, is eminently extensive in its type ; sugar and 
rice : both these forms of cultivation are dependent on adequate irrigation ; sea 
water is injurious and must be excluded, hence sea defences and elaborate systems 
of sluices and pumping stations; rain and flood waters are stored in conservancies 
situated aback of the cultivation, to feed thousands of miles of irrigation canals 
which riddle the coastlands. Thus ideally favourable breeding sites are provided 
for mosquitoes, at all seasons, and breeding continues the year around with 
greater or lesser intensity, according to. the temperature and the individual 
characteristics of each species. 

In this Colony, perhaps more than elsewhere, the connection betweon agri- 
culture and malaria is intimate : there can be no doubt that the prevailing forms 
of cultivation, rice and sugar caue, influence the malaria problem adversely. 

. Malaria is a mosquito borne disease ; not all mosquitoes are capable of trans- 
mitting it; this pernicious role is exclusively restricted to mosquitoes of the genus 
Anoplwles. These facts can now be regarded very nearly as common knowledge; 
but it is not, as yet, at all appreciated that the carrier problem must be restricted 
to yet a much mere limited field : only a relatively small number of species, in 
fact, out of the many included in the genus Anopheles have practical imimtanee 
in the transmission of malar ia. 



76 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [IX, 2. 

Some speoies of Anopheles are not sasoeptible to infection, even when 
repeatedly fed on patients harbouring abandant malaria parasites in their 
blood, in the phase suitable for mosquito infection. In others, infection occurs, 
bat the parasite appears unable to undergo its full development and fails to reach 
the stage in which' it again becomes infections to man when inoculated in the 
blood stream through the mosquito’s bite. Such species of Anopheles, evidently, 
are constitutionally unfit for the transmission of malaria and their practical im- 
portance to the malariologist is nil. 

There are other species of Anopheles which in the laboratory can be 
infected with malaria with the greatest ease, but under natural conditions very 
rarely become infected as they bite animals selectively and man only as the 
exception. It is very unlikely that an individual mosquito, belonging to one of 
these “ zoophylous species ”, should bite man repeatedly at the interval 
required for it to become infective. Transmission of malaria by such species 
is evidently possible, but sufficiently unusual to lose much, if not all , practical 
importance. 

With gome species zoophyliu is a constant characteristic ; in others it may 
be acquired under favourable conditions ; thus a same species of Anopheles 
may be found to be a dangerous carrier in one region, whilst it is zoophylous, and 
therefore harmless, in others. Such is the case with the species Anopheles 
muculipennis, the main vector of malaria in Europe ; with the advent of inten- 
sive agriculture', which implies an abundance of livestock and animal shelters, 
this species tends to restrict its biting activities to the shelter of stables, cowsheds 
and pig-sties ; “ biological varieties ” evolve which do not attack man, and thus 
lose all importance as natural vectors of malaria. 

In England, in the districts where malaria, in a not too distant past, used to 
be endemio, A . maculipennis still abounds, not in homes but in animal shelters. 
We have seen it in enormous numbers in Surrey pig-sties and cow barns. Like- 
wise in Italy zoophylous biological varieties of this species exist at present in 
localities which were malarious only a few decades ago. 

In the American tropics, some .‘10 or 40 species of Anopheles have been listed 
by various authorities. These species vary widely in their geographical distribu- 
tion, their feeding and breeding habits and in their infectability to malaria. 

We have outlined these facts as they constitute the basal principles on which 
rational malariology is founded. 

In any given malarial locality the following are the first and basal problems 
to be resolved : 

(U The identification of the local existing Bpecies of Anopheles. 

(2) The distribution and incidence of such species in relation to the dis- 
tribution and incidence of malaria, 









MALARIA m BRlflS tt GtJIANA. 11 

(3) The detailed biology of each species with special regard to breeding, 
biting and flying habits* 

Once these data are folly acquired we have at oar disposal the means for 
intelligent, direct and, above all, economical malaria prevention : onr whole effort 
can be concentrated on the control of the species which is or are the proven vectors 
oj malaria in the region ; the others may be ignored in all safety. 

The conditions we have found in this Colony are a very striking example of 
this definite limitation of the malaria problem to a single Anopheline specks. 
The practical importance of this fact is too obvious to be stressed : it means that 
for the control of malaria in British Guiana we must deal with a single species , 
subject to certain definite limitations in its breeding habits ; we can, on the 
other hand, ignore other species of Anopheles, much less exacting, as we shall 
see, in their breeding requirements. In consequence of their greater adaptability 
these latter species are very much more widely distributed and abundant so 
that, given the physical configuration and climate of the colony, their control 
would be practically impossible. 

The whole classification of tropical American Anophelines is, at present, 
under revision as methods have been perfected greatly of late years ; the 
anatomical characters of the males have acquired great taxonomic importance. 

It is by no means possible, at present, to give a complete catalogue of the 
local species of Anophelines ; we can only mention those which we have 
encountered in onr personal experience of some 15 years, From lfi34 to the 
time of writing we have examined and identified over 20,000 specimens collected 
from numerous coastal localities between the Essequebo and Corentyne estuaries 
and from the interior, on the Demerara, Essequebo and Potaro rivers. We are 
indebted to Mr. and Mrs. H. E. Turner for a collection of 70 Anopheles captured 
in various localities on the Bupununi Savannahs in August 1030. 

Three species of Anopheles are widely distributed and very abundant in 
the Colony. They all belong to the sub-genus Xyssot hynnis the members of 
which can easily bo recognized by the silvery white extremities of their hind 
legs. We will not go into detailed descriptions, limiting, our exposition strictly 
to the main differential characters which are of practical importance in the field 
and in the laboratory for routine identification purposes. The more important 
of these characters are very plainly visible in our series of micro-photographs. 

A . tarsi maculatus . This species can easily be identified with the help ot a 
simple magnifying glass, as it possesses a black spot or ring at the base of the 
last segment of the hind logs. It is ubiquitous : we have specimens captured in 
houses in Georgetown, from West and East Demerara, from Western Berbice 
and the Corentyne coast, where we have found it particularly abundant. It 
is occasionally found along the rivers in the interior, wherever some clearing 
of the forest has been effected. This species is also represented in our collec- 
tion from tlje Hupununi. 



78 


AGRICULTURAL JOURNAL OF feRItlSH GUIANA. 


[IX 2. 


We have also observed the occurrence of a known variety of A . tarsima- 
culatus characterized by having a larger portion of the hind legs white ; (the 
black portion of the 2nd tarsal segment is represented by only a narrow ring 
at its base). We have specimens of this variety from the Berbice Estuary and 
from the Rupununi Savannahs. 

The existence of A. tarsi maculat us in the Colony has long been known. 
Bodkin and Cleare observed that it abounded in localities which were only 
mildly malarial. It has been regarded as the principal carrier of the disease on 
the coast. Flu and more recently Bonne and Bonne Wepster expressed the 
same opinion as regards the coastland of Surinam, 

In our own experience, though the larva* of this species are by far the 
most commonly and easily found, ^4. tarsi, mandat us is relatively rarely caught 
in the dimly lighted native houses : but it is not at all uncommon to capture it 
in bright, electrically lighted estate hospitals or staff houses. It 'is evidently 
attracted there by the light as myriads of other winged insects. A . tarsnua- 
rnlatus becomes active at dusk ; but occasionally and in proximity of its breed- 
ing sites, it may attack in large numbers and in full sunlight when disturbed from 
its resting places in high grash or bushes. It can be found at all seasons, 
throughout the year, but is much more abundant during the warmer months 
from May to October. 

A. tarsi mat ulatus abounds in stables, cattle and sheep pens, and can easily 
be caught on horses and cattle in the open, after sunset. With Mr. Komp, of 
the United Stages Public Health Son ice, in July 1030, we observed this species 
in countless thousands in cattle sheds at Gibraltar, on the Corentyne coast, some 
10 miles east of New Amsterdam. This locality is practically free from 
malaria. The sheds were open to the strong sea breeze and the Anopheles were 
crowded over the timber sills forming tbe base of the building, some 6 inches off 
the ground ; many were actually resting on the rough, damp clay floor evidently 
resisting the strong breeze with considerable difficulty. Males were also 
piesent in large numbers, this fact indicating the close proximity of their 
breeding sites in the extensive Iron Hand brackish marshes. A. iarsunucututus 
haunts savanna] countries open to sun and wind : it is a hardy species and its 
resistance to the desiccating action of the wind is very considerable. 

This species shows remarkable adaptability and latitude ill the choice of its 
breeding sites ; irrigation canals, drainage trenches, flood fallowing cane fields, 
rice fields, flooded pastures and savannahs, swamps, marshes, ponds, rain water 
collections of all kinds, puddles, cow holes, ruts, clean water and dirty water, 
salt, brackish and rain water, strongly acid, neutral and alkaline water, all 
suit it and in all it flourishes. Brackish waters are probably its favourite 
breeding sites, lienee its abundance in the extensive salt marshes of the 
Corentyne coast froutlands. The pH of waters in which *4. farsiutarulatus was 
found breeding ranged from 4 to 7.8 ; the sodium chloride concents from 
g. 0.005 to g, 2S.000 per litre* 



Fig, 4.— Pupae of : % 

(a) A . albitarsis (note scoop-shaped breathing trumpets). 

• (b & c) A. tlarlinyi (the margins of the breathing trumpets are deeply indented). 






MALARIA I ft BRITISH OtTIANA. 


7£) 

The two following species, A. dibit arsis ahd A . darling ! , though extremely 
common, have not previously been identified in this Colony, being in the past 
regarded as a single kind under the erroneous designation of A. argyritarxi * . 
This confusion is easily explained by the close similarity among the adults of 
the Nyssorhyncus group ; on the other hand, the differentia) characters which 
are revealed by closer examination are so evident and distinctive that it is 
surprising they should have eluded detection for so long. 

A . argyritarsis is a valid species first described in Panama ; its importance 
as a malarial vector was there regarded as of small moment. It occurs in 
Brazil, but, up to recently, even in that country, it was currently and widely 
confused with the following two species. 

Exact information on its geographical distribution is still lacking : so far 
we have failed to find it in this Colony. This, evidently, does not exclude 
definitely its presence, but we feel authorized to state that even if it does occur 
in small numbers; or in restricted foci, the importance of this species, in relation 
to the malarial problem in British Guiana, is nil. 

A. albilarsis : the adult insects of both sexes can be easily recognized by 
the presence of two parallel rows of conspicuous white scales on the ventral 
surface of the 1st abdominal segment (l.s/ slrrmtr). In dried specimens, 
through retraction, the sternite is usually concave so that these lines of scales 
acquire a V — like or converging disposition. Fig. I shows the latero- ventral 
aspect of a female -1. nlb*(an>*s , one of the rows of scales we have described is 
clearly visible. 

Fig. II demonstrates the differences in the wing markings of -l. albUamx 
and .1. darling* : the different disposition of white and black markings of the 
the costa, or anterior wing rib, at its base, should be noted : in the former (a) 
two small black spots stand out in contrast on the white background ; in the 
latter (b) the colour scheme is reversed and two small light coloured spots 
stand out on a black background. The light coloured wing scales of A. alfntars*s 
are white ; those of *1. darling! are golden yellow. 

The larva* of A. fanunandatns and A. affntaisis though very similar, can 
be differentiated in the laboratory on the characters of some of their ornamental 
hairs, but for this purpose a certain amount of experience is necessary. The 
pupm of these species vary considerably in colour, from dark to light brown, 
yellowish or bright green ; we know of no good character for their differentiation. 

The distribution of A. alhilarvis in the Colony is wide ; we have collected 
It in West and East Demerara, in Western Bcrbiee and on the Corcntyno coast ; 
we have never observed it in the forest areas of the interior and* we doubt its 
existence in such districts. Ninety per cent, oi our specimens from the ltupu- 
nuni belong to this species. 

A . albikims presents a well marked seasonal incidence : it appears early in 
May and continues throughout the warmer weather to October or ifovember, 



80 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 2. 

fluctuations occurring from year to year according to variations in the seasonal 
distribution of the rainfall. It is very unusual to find this species between 
December and April. 

The favourite haunts of A . alhi tarsi s are open savannahs and pastures 
where cattle abound. It occurs in great numbers on the back dams of Western 
Berbice estates and on the Abary savannahs. It naturally flies and feeds after 
dusk, but if disturbed from its shelter in the grass or bushes it will attack 
viciously and in full sunlight. Hiding on the Abary savannahs and, we under- 
stand, in the Rupununi, is often made very unpleasant by the attentions of this 
mosquito. It is little affected by high breezes and, on the whole, we have found 
it a much hardier species than the following one. 

In the selection of its breeding sites it appears to favour large bodies of 
water well exposed to the sun ; flooded savannahs and pastures ; flood fallowing 
canefields ; ricefields ; irrigation canals, etc. It also occurs occasionally in ponds, 
small drains and temporary rain water collections. 

The waters in which it breeds are clean, slightly acid or neutral in reaction, 
with a low content in soluble salts (pH range G.G to (5.9 ; sodium chloride 18 to 
30 milligr. per litr^). 

*1. durhnyt : the adult insects of both sexes in ttys species present the fol- 
lowing differential characters : the distal half of the 2nd and all of the 3rd, 
4th and 3th tarsal segments oi the hind legs are snow white ; the wing mark- 
ings are distinctive, and there are no white scales on the 1st abdominal sternite. 
These characters have already be«»n described when dealing with *4. albit«rsi« 
aud are well illustrated in Figs. I and II. 

The larva of .4. darlnigi presents a very striking and unique character in 
the form of two long, straight bristles, surmounting papilla' placed on the dorsal 
plate of the spiracular or breathing mechanism. These bridles are directed 
dorsally so that when the larva lies horizontally just below the water surface, 
they protrude through the surlace film ; they are very clearly shown in Fig. Ill 
and can be detected already in the v 2nd and 3rd stage of larval development. 

The pupa of A. durVnnji is equally well characterized ; its colour is always 
dark brown ; the breathing trumpets which in -1. iarxiiHaaifahtx ami A. albdttr - 
nix are delicately ctntinizcd with a plain scoop-like shape, in A. darlinyi have a 
very much more elaborate structure : the trumpets are heavily chitinized, more 
open and present on their lateral margins deep indentations which give rise to 
two very characteristic finger-like projections. Our micro-photographs illustrate 
these characters more effectively than any description (Figs. IV, V, and VI ). 

.1. (Uirliwji was first described by Root at Bahia, Brazil, in HhJG: the 
investigations of Shannon, Davis, Kumm, Benniroch and others have demon- 
strated its wide distribution in equatorial South America. It ranges from the 
foot hills of the Andes throughout the Amazon valley to the Atlantic seaboard ; 
it occurs in Venezuela and we have established its presence in British Guiana ; 
itA southern range is not, as yet, fully determined. 



PLATE in. 



Flu. (5 Breathing trumpets of A. datiirvji. 







Malaria in British guiana. 


81 


In the Colony it is the Anopheles of the forest areas of the interior on the 
tidal and flood rivers ; we have collected it in large numbers on the mid and 
upper Demerara, on the Essequebo and Potaro Rivers. On the coast it is often 
associated with A . tarsi maoulatus and A . albitarsis but its general distribution 
does not follow these two species. In some coastal localities it is extremely 
abundant, particularly on the estuaries of the Demerara and Berbice rivers and 
on the West and East Coast of Demerara. So far we have had difficulty in find- 
ing it at Cane Grove and it is definitely rare along the sea coast of Western 
Berbice. It represented only 8.3% on 097 Anopheles captured in houses on Bath 
Estate between 1934 and 1937. This species occurs also in our Rupunnni collec- 
tion : a single specimen was captured on human bait in a partly forested district 
at the foot of the Kanuku Mountains. 

The three species we have described, A . tarsi mnculatu>% *4. albitarsM, and 
A. darling i , between them, account for 99.9% of the 20,000 adult Anopheles we 
have collected and identified. All the larvae and pupae we have examined, 
without exception, belong to these three species. 

Other Anophelines, evidently, occur in the colony but always in small 
numbers and it is quite exceptional to capture them in houses. We have some 
female specimens of two different species belonging to the Arribaha gut group ; 
they were all caught in wooded localities, on the the mid-Demerara, on the 
Berbice Estuary and in the Rupununi District, most of them on animal bait in 
the open ; larvae and males have not, as yet, been found and for this reason 
their exact identification is still doubtful. 

A. (Stelhwmjidj nimbus has been reported from the Colony and Komp 
found it common in the forest at Kartabo in July 1936. 

It is quite evident that these and eventually other rare, or at least 
Uncommon, species, can havo no practical importance from a maiariological stand- 
point. Malaria in British Guiana is extremely prevalent and widely distributed} 
its carrier or carriers must therefore, evidently, be equally common. 

We have seen that A. tarsi maculat us, .4. albitarsis and A. ddrhngi are 
all extremely numerous with a wide range of distribution, all of them, therefore 
in this respect could adequately fill the role of malaria carriers. 

The relative importance of each one of these species in regard to thd 
transmission of malaria, under local conditions, will next be treated. 


^ To h Conti nut tf ) 



RESULTS OF PADI VARIETAL TRIALS AND EXTENSION 

WORK, 1937. 

BY 

P. BURNETT, M.C., M.A., 

Deputy Director oj Agriculture. 

During the Autumn Crop of 1937, fourteen variety trials wore laid down, 
six standard trials containing the same varieties for trial at various centres in the 
Colony, and eight trials with promising varieties. The sites of these experiments 
were as follows: — 

Berbice : Whim. 

No. 63. 

Demerara : Georgetown Rice 
Station. 

Hope, East Bank. 

Vreed-en-Hoop, 

Essequibo : Henrietta. 

Leguan. 

Wakenaam. 

The results are presented in Tables I and 11. 


Under the supervision of Mr. J. D. 
Gillespie, Agricultural Superintendent. 

Under the supervision of Mr. E. M. 
Peterkin, Agricultural Superiutendent. 

Under the supervision of Mr. H. D. 
Huggins, Agricultural Superintendent. 

Under the supervision of Mr. A. A. 
Abraham, Agricultural Superintendent. 

Under the supervision of Mr. E. G. 
Benson, Agricultural Superintendent. 



Standard Trials, 


RESULTS of paDi varietal TRlAlia. 


85 




Table II. 

Padi Trials — X e\v Varieties. 




RESULTS OF PADI VARIETAL TRIALS. 


85 


The following conclusions may be drawn from Table I. : — 

(a) Vreed-en-Hoop. D99 is significantly superior to all other varieties 
except D114 , which surpasses the rest except Demerara Creole, 
D109 and DUO. 

(b) Leguan. There is no significant difference between DllO, Kahja- 
man, No. 79 and DU4, but the first three are significantly superior 
to the other four varieties tested. 

tc) Wakenaam. Again the first four varieties D114, D99, DllO, and 
No. 79 are equal to one another. The other varieties tested are all 
inferior to these with the exception of Kahjaman, which is surpassed 
only by Dll 4. 

(d) Whim. There is again equality among the first four varieties 
Kalyaman, Demerara Creole, DllO and Dll 4 of which Kalyaman 
alone surpasses the rest. D99 is significantly inferior to all the 
others. 

(e) No. 03, Berhiee. Equality again exists between the first four 
varieties Dl 14, D99, Kahjaman, and DllO, of which DU4 alone 
surpasses the rest. D109 is surpassed also by D99 and Kah/aman. 

The following conclusions may be drawn from Table II. : — 

(a) floor get men ( Experiment No. l). D114 was superior to all the other 
varieties tested except D221, D97 (B) and Demerara Creole, 

(b) Georgetown ( Experiment No. 2). D99 far outyielded the other 

varieties tested. Demerara Creole and No. 79 were disappointing. 

(c) Georgetown ( Experiment No. 4). D114 was outstandingly superior. 
Bl and Demerara Creole were bracketed second, while the other 
four varieties were significantly inferior. 

(d) Georgetown (Exjteriment No. .5). Dll-5 was superior to all the other 
varieties, No. 79 again disappointed. 

(e) Knot Bank, Demerara. D114, Demerara Creole and D109 were 
bracketed first, of which 1)114 was significantly superior to the rest. 

(f) Henrietta (Experiment No. /). Dl 14 was superior to the other 
varieties tested except D99, which in turn surpassed the rest except 

Dl09. 

(g) Henrietta (Exi>eriment No. 2). D114 was again superior to the 
other varieties tested except DllO, which in turn surpassed the rest 
pxcept D109, 



36 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 2, 

SUMMARY OF ALU TRIALS, 

A general comparison between all the varieties tested during 1937 is shown 
in Table III, which is shown graphically. The average yields per acre of the 
varieties are calculated as percentages of the Demerara Creole yield which is 
taken as the standard, 


Table III. 


Summary of 1937 Variety Trials. 


1 

Variety 

No. of 

Trials. 

Average Yield per acre 
Compared with Demerara Creole. 
(100.0) 

D114 

11 

117.1 

DUO 

9 

110.2 

D99 

10 

106.1 

D91 

9 

1 103.7 

D109 

11 

1 103.6 

Kalyaman 

10 

103.0 

Dll 6 

1 

, 102.1 

Blue Stick 

2 

. 99.0 

No. 79 

H 

97.3 

B1 

1 i 

96.5 

D88 

3 

92.6 

D97 (B) 

2 ! 

90.2 

D221 

2 

90.0 

D89 

o 

hj 

89.1 

D90 

1 

88.9 

DUS 

2 1 

88.(5 

D92 

o 

87.2 

B3 

1 

87.2 

D228 

l 

85.4 

B6 

1 

83.0 

B4 

1 

81.9 


Blue Stick Strain Trial. 


Four strains of the Blue Slick variety were selected and tried out in a trial 
in 1936. This experiment was repeated in 1937, and the results are shown in 
Table IV. . As in 1936, no significant difference was revealed between the yields 
of the various strains, and it is concluded that the Bine Stick grown on the 
Henrietta Station is pure, so that no further advantage can be gained by selection 
within the variety. 



RESULTS OF FADJ TARIETAL TRIALS. 


87 


Table IV. 


Site 

Henrietta 

Layout 

5X5 Latin Square 

Strain 

Padi per acre, lb. 

Ordinary Blue Stick 

l 

2808 

Strain 4 

2760 

Strain 2 

2692 

Strain 1 

2612 

Strain 3 

2552 

Significant Difference P = .05 



Long Grain Trial. 

Four long-grained rices were received at the Henrietta Station in 1037, and 
they were put in a trial to see how they compared with the ordinary Blue Stir h 
cultivated on the Essequibo Coast. The results of the trial Bhown in Table V 
reveal no signitioant difference between any of the varieties. 

Table V. 


Site 

j Henrietta 

Layout 

1 

5 X 5 Latin Square 

i 

Ordinary Blue Stid< 1 

4020 

Seymour Padi 1 

3768 

Jaisingh Padi 

3760 

Ramjess Padi 

Sue’s Padi, 

3560 

3520 


Significant Difference P = .05 









88 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 2, 

Varietal Notes, 

The following is a summary of the past performances of some of the more 
important varieties : — 

Demerara Creole. In 1930 this variety came third in the Essequibo and 
Berbice trials, fifth in the Demerara trial. In 1931 it came third in the 
Demerara, fifth in the Essequibo trial. In 1932 was fifth in the Demerara, third 
in the Essequibo trial. In 1933 was fourth and fifth in the Demerara trials, 
fourth in Essequibo, In 1934 it was fifth in two Demerara trials, seventh in 
Essequibo. In 1935 it was extensively tried in ten trials, and could surpass 
No. 79 only four times. In 1936, in twelve trials, it was beaten by No, 79 ten 
times, and in eight trials with Blue Stiel was beaten six times. 1937 selections 
improved on the 1936 performance and outyielded No. 79 in nine trials out of 
fourteen. 


No. 79. In 1930 this variety outyielded ail varieties in two trials, and came 
second in another. First place was again taken in two trials in 1931. In 1932 this 
performance was repeated, and in 1933 again it proved superior iq three trials. 
In 1934 it came second in two trials, but made eighth place in another. In 1935 
it gained two firsts and three seconds in ton trials, followed this up in 1936 by 
surpassing Demerara Creole ten times in twelve trials. In 1937 it unaccount- 
ably failed, and its performance was very poor, being surpassed by Demerara 
Creole nine times in fourteen trials. 

Blue Stick. This variety did well in one trial in 1930. Tried twice in 
1931 it was second in Essequibo but sixth in Demerara. Tried only once in 
1932, it came second in Essequibo. It jumped up to a consistent second place 
in each of three trials in 1933, and repeated this good performance in 1934 
by coming first in Demerara and second in Essequibo. In 1935 its yields 
were only average, but it did extremely well in 1936, when it surpassed 
Demerara Creole six times out. of eight, and No. 79 six times out of ten. In 
1937 it was tried only twice, at Essequibo, and came sixth each time. 

V. 114. This variety made its debut in 1934, and came second in its one 
trial. In 1935, placed in six trials, it outyielded Demerara Creole every time. 
Blue Stick four times and held its own with No. 79. It put up a wonderful 
performance in 1936, gaining four first places, three seconds, and two thirds in 
thirteen trials, and in 1937 this was even bettered when it came first in eight 
trials out of eleven, being beaten by Demerara Creole and No. 79 only once. 

D. 110. This variety first appeared in a trial in 1935, when it was fourth, 
yielding higher than Demerara Creole , No. 79 and Blue Stick. In 1936 it was 
placed in eight trials and surpassed Demerara Creole every time and No. 79 four 
times* In 1937, appearing in nine trials, it snrpassed No. 79 eight times, and 
Demerara Creole three times. 



RB8ULT8 OP PADI VARIETAL TRIALS. 


89 


D. 99. Like D. 110, this variety oame oat in 1935. In three trials it came 
first twice. Appearing in only two trials in 1930, it was first in both. This 
splendid performance was continued in 1937, when in ten trials, it gained two 
firsts and five seconds, surpassing Demerara Creole and No. 79 seven times each ; 
only the outstanding D. 114 could give better yields than this variety during 
this year. 

Miscellaneous Trials. 

A trial was carried out at Henrietta in which transplanting seedlings of 
different ages was tested oat. The results of this trial are shown in Table VI. 


Table VI. 


Site 

Henrietta 

Layout 

5X5 Latin Square 

Age of Seedlings 

i 

Padi per acre lb. 

3 weeks old 

4072 

4 ,, ,, 

4008 

5 .. 

3904 

Double Transplanting 

3800 

6 weeks old 

3704 

Significant Difference P = .05 

188 

_ _ 

„ 


The following conclusions may be drawn : — 

(a) There is no significant difference bet weed’ seedlings transplanted 
3, 4, or 5 weeks old, 

(b) Double transplanting and transplanting seedlings 6 weeks old are 
both inferior to seedlings transplanted 3 weeks and 4 weeks old. 

(c) Transplanting seedlings 5 weeks old is not superior to double 
transplanting, but is superior to transplanting seedlings 6 weeks 
old. 

The results of this experiment agree with those obtained in 1935, both 
showing no significant differences between transplanting seedlings 3, 1, or 5 
weeks old, with, however, a trend in favour of the younger seedlings.* The 
results of 1936 are in conflict with these two results. A further trial may give 
some definite answer to this problem, 



90 AGRICULTURAL JOURNAL OR BRITISH GUIANA. [IX, 8, 


Table Y1I presents the resalts obtained with planting different numbers of 
seedlings per hole. 


Tablb VII. 


Site 


Henrietta 


Layout 


5x5 Latin Square 


Number of Seedlings per hole 


Padi per acre lb. 


5 

3 

2 

1 


28(H) 

206 

2460 

2436 

2388 


Significant Difference P = .05 


11)4 


There is no significant difference between the yields obtained from 7 and 
5 seedlings per hole. Both, however, give significantly higher yields than 3, 
2 or 1 seedlings per hole. These results are in direct contrast with those of 11*36, 
in which experiment fewer seedlings per hole were significantly superior to 
greater seedlings per hole. Farther investigations must be carried out to obtain 
definite information. 


Purity oi Padi Cultivations. 

Daring the 1937 Autumn Crop the usual estimations of purity of padi 
cultivations were carried out in the various districts. These estimations are 
shown in tabular form in Table VI 11. In each district can be seen at a glance 
the total acreage under rice cultivation, and the areas of pure line and purities 
of approximately 90%, 90% — 75%, 75% — 50%, and under 50%. These areas are 
calculated in percentages of the total acreage, and from these figures are derived 
the percentage area of a district which shows purities greater than 75% and 50% 
respectively. 

Information regarding the area of seed farms supplying each district is also 
given* 



RESULTS OF PADI VARIETAL TRIALS, 


91 




92 AGRICULTURAL JOURNAL OR BRITISH GUIANA. [IX, 2. 

Progeny Rows, 

1. Georgetown Experiment station. 

At the end of the 1937 Autumn Crop gome of the varieties were not 
considered worthy of being kept any longer in the progeny rows. These pedis 
were under observation for several seasons, and their characters proved to be of 
little value. The following is a list of the varieties which were discarded ; — 

Dis< ari>kt) Varieties, 


Variety, 

Date 

Received, 

T 

H6 

No record 

No. 77 


No. 7ft ' 

Sept. 1928 

(Ian ka san navari 

Kristna Kata Kului 

Peru 1 

4.12.29 

Sago 

30.9.31 

Sonacalif j 

,30 3.33 

Louisiana I 

18 7 33 

ok shot ; 

17.hl.33 

Theik Pan 


Jujjai 

27.10.33 " 

Prong 3G 


Basmati 

7U 33 

Mushkati 7 

„ 

Magoi 


Kataktara 

10.1*34 

D 154 

13 1 34 

D 157 

3.2.34 

D 158 

D173 

19 £34 

D 175 

D 181 

11 

D 190 

D 191 

I) 195 1 

164.34 

Orealla 1 

2H.8.34 

Oerang-Oerangan 
Paloe Alessoe 

30.K.34 

Maoemi 

1 

j * 1 

I) m 

D 235 

1 1011.34 

L‘237 

19.11.34 

B 2 

1931 

B 8 

1 

C 1 

1 « 


Origin. 


Reaaons for 1 No of Seasons 
Discarding. j Tested. 


No record I Poor yield 7 

M „ i „ „ 

. 7 

Madras, India Poor yield, short grain 7 

„ „ Poor yield, short grain 7 

Peru Poor yield, awned grain 7 

Her bice Small grain ft 

Fiji Islands /Poor yield r 0 

Louisiana „ „ ' j G 

Mandalay 'Poor > ield, small grain] o 

Poor yield, small grain] f> 

Larkana, Sind Poor yield, \ery thin i 5 

, K*rain 

1 , » Poor yield, small grain 4 

jPunjab, India Poor yield, very thin G 


»« 

grain 

Poor yield, very thin 
grain 

5 

Assam, India 

Poor yield, small grain 

G 

Poor yield 

4 

Bombay 

Poor yield, small grain 

4 

Tanganyika 

Poor yield 

4 

‘Central Pro- 
' vinces, India 

iPoor yield 

5 

4 

n 

|Poor yield, small grain 

4 

United Pro- 
vinces, India 

Poor yield 

| 

4 

Tanganyika 

Pcor yield, thin grain 

4 

V 

Poor yield, thin grain 

4 

1 

11 

,Poor yield 

11 V 

4 

;Orealla, Oor- 
entyne 

4 

,.Tava 

Poor yield 

3 

11 

Poor yield, awned grain 

3 

11 

Sind, India 

Poor j ield 

3 

'Poor yield, thin grain 

4 

» 11 

Poor } ield. thin grain 

4 

jrsorth Borneo 

Poor yield, small grain 

4 

Hybrid of D (\ x'Poor yield 
| Americano 1000 

3 

Hybrid of Mexi 
can Edith x D.O 

i> i> 

4 

3 



Comparison between yields of varieties tested and Dem 



l P*o 



f>4 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [l£, 2. 

The following list comprises the total number of varieties which are now 
being tested ut the Georgetown Experiment Station. The table shows the 
varieties* with places of origin and dates received, the number of seasons they 
have been tried, their average yields per thousand plants over these seasons, and 
their grain characteristics, whether long, medium, or short. 


Varieties Under Test at Georgetown Experiment Station. 


Vai iety. 

Date 
reeel \ oil. 

Origin. 

No. of 
seasons 
i tested 

Yield 
per 1,000 
plants, 
lb. 

Type of Grain. 

Demerara Creole 

No record 

No record , 

7 

61.1 

Long 

Blue Stick 



0 

62.6 

Medium 

McKenzie Large 
McKenzie Small 

44 


7 

03.2 

44 



7 

70.7 

Short 

H7. 


„ i 

6 

61.2 

Medium* long 

No. 75 

1* 

Probably i 

7 

54.7 

No. 76 


India 

Local 

7 

56.9 

Long 

No. 79 


selection 

7 

01 0 

Medium 

Rnmcajara 

Sept.' 1 929 

Madras, 

7 

61 4 

Medium, broad 

Ak Kulu 

7 

74.7 ' 

Short 

Air,. 34 

Oct. 1 1128 

India 

Burma 

7 ! 

56.0 

Medium-long 

014. 31 


7 

67.1 

Short, broad 

Toledo 

1 17.il/2S 

British 

8 

25.0 

Medium, broad. 

District 

Lead Rice 

11.12.29 

Honduras 

Mr. Abdool 

7 

61.4 

1 Short, broad. 

No* 36 

28.1.30 

Ray man 
, Trinidad 

l 7 

59.4 

' Medium, broad. 

No. 11 ; 

1 


! 6 

74.5 

Short, broad. 

Kaly aman 



1 7 

, 54.0 

Long. 

Rupununi 

1931 

Rupununi 

8 

25 6 i 

1 Medium, broad. 

White Pin i 

30.9.31 

! Berbicc 

7 

22.4 

44 4J 

Minulabon j 

11.4,32 

' Philippine 

! 6 

62.5 

Medium 

DH8 i 

12.10 33 1 

j Islands 
| Local selection. 

5 

63.7 

, Medium, Long. 

1 

D89 

„ 

' W.C. Demerara. 

I 

1 44 

! 5 

1 71.9 

1 

I Long. 

1)9) j 


1 14 

, 5 

1 77.9 

1 44 

D 91 


1 H 

, 5 

63.6 

1 44 

I) 92 



6 

, 70.6 

Medium-long, 

D 94 

1 

1 ” 

1 6 

69.6 

j Medium. 

D 95 

i 


1 5 

53.6 ‘ 

1 

D 97 A 

1.10.33 

Local selection. 

1 5 

j 61.2 

14 

D97B 


Expt. Station 

t M 

1 

1 3 

1 69.7 

44 

D99 


1 7 

1 „ 

1 4 

70.9 

44 

D 100 

n.ioiss 

44 

4 

61.2 

Medium-long. 

Karimganj 

Mandalay 

< 5 

84.8 

Short 

D 108 

D 109 

18.10.33 

1 Local selection. 
W,C. Demerara. 

)t 

5 

1 6 

78.9 

73.4 

Medium 

Medium-long 

D 110 

>4 

p • 

' 5 

68.5 

Medium. 

0114 

4, 

tl 

6 

68.0 

Medium-long, 

r> ii5 

44 

1 * 

5 

86.3 



kagULtfS Ol* PADI VABIfiTAL TltlALS. 


Variety 

Date 

received. 

1 

Origin. 

No. of 
seasons 
tested. 

Yield 1 
per 1(KM) 1 
plants, 1 
lb. 

P 116 

18.10.33 

Local selection, 
W.C. Demerara 

5 

73 6 

Unity 

9.11.33 

Unity, E.C. Dem. 

5 

88.3 

D 136 

10.1.34 

Assam, India 

Tanganyika 

4 

54.8 

D 160 

„ 

3.2.34 

4 

57.3 

D 156 

5 

58.5 

D 160 

28.2.34 

Bengal, India 

4 

59.2 

D 162 

4 

69.4 

D 176 

19.3.34 

Central Pro- 
vinces, India 

4 

63.5 

D 183 

16.4.34 

Madras, India 

4 

74 8 

1) 184 



4 

510 

D 186 


Tanganyika 

4 

57.9 

D 193 

17.5.34 

4 

69 1 

I) 205 

North Borneo 

4 

53.0 

Kao Bang Pra 

17 7.34 

Siam 

4 

37.7 

J) 221 

13.9.34 

Local selection. 
Berbiee 

4 

67 6 

D 222 


, 

4 

53.9 

I> 224 


t , 

4 

67.2 

P 225 



4 

57.2 

D 228 

2.10.34 

North Borneo 

4 

63.7 

P 236 

19 11.34 

4 

47.8 

D 23H 


,, 

4 

62 0 

D 239 

27.11.34 

Local selection, 
Essequibo 

3 

81.7 

1) 242 

3.11.34 

Local selection, 
W.C. Berbiee 

3 

56.1 

P 243 


It 

Local selection, 
Essequibo 

3 

59.8 

D 244 

27.11.34 

3 

78.2 

D 245 

Novr. 1934 

Local selection, 
i Berbiee 

3 

59.5 

P 246 

7.10.35 

Local selection. 
Expt. Station. 

i Surinam 

o 

. 71 6 

P 247 

10.10.35 

o 

HI. 3 

P 248 

2 

I 31.3 

P 249 

9.10,35 

1 

, 

•j 

13.4 

P 26*) 

| Local selection, 
Wakenaain. 

2 

j 73.9 

1 

P 261 

i 

Local selection, ' 1 
Leguan. 

2 

• 7') 5 

I) 253 

! 

| 15,10,35 

I 

2 

!• 

1 1 

P 254 ! 

! 

i • « 

2 

85.6 

D 255 

25.10,35 

Local selection, 

I Vreed-en-Hoop. 

2 

i 

i 110.2 

P 256 


2 

i 92.9 

D 257 

i 11 

1 " 1 

•2 

I 106.2 ! 

D 258 

i *’ 

tt 

2 

82.2 

D 259 

4.12.36 


2 

85,1 

D260 

Local selection, 
W.C. Berbiee. 

2 

38.4 

i 

D 261 

4 

11 

2 

t 54,1 i 

P 262 j 


1 „ 

2 

46.6 

D 263 


1 Local selection, 
Skeldon. 

2 

37.2 

D264 

11 

1 Local selection, 

| Skeldon. 

o 

35,7 

D 266 

8 3.36 

Sierra Leone 

1 

46.4 i 

P 267 • 



1 

4.5 > 

P 268 

1* 


1 

25.0 

P297 

Novr. 1937 

Local selection, 

... 

,,, 

Padi, B*ce. 

1936 

Expt. Station. 

liOOftf 8$l6CtlOD| 

Berbiee. 

2 

100,7 

1 


95 

Type of 
Crain. 

Medium-long 

Medium 

Short 

Short 

Medium -long 
Medium 

Short 

17 

Medium 

M 

ft 

Long 

Medium-long 

Medium 

Long 

Short, broad 
Medium 

it 

Medium-long 

Medium 

Short 

Medium 

Medium. 

Medium-long. 

Medium 

Medium-long 

11 

Medium -long. 
Medium, 

Lon^. 

Medium, 

1' 

Medium- long. 
Short, 

it 

t* 

Long. 

Medium-long, 



AGRICULTURAL JotTRNAL OF BRITISH GUIANA. 


[IX, 2. 


% 



' 

Date 

received. 


No. of 

Yield per 


Variety. 

Origin, 

seasons 

tested. 

1000 plants, 

Type of Grain. 

Nickerie Patna 

1935 

Local selection, 

2 

75.4 

Medium-long 



Berbice 



Seymour S. 

1936 

Mr, Seymour 

1 

76.8 

Long 

No. 1—37 

1931 

Hybrid— D.C. x 

4 

72,1 

Short 



Americano 1600 




„ 3-37 


St 

3 

607 

Short 

„ 4-37 


99 

3 

64 5 

Medium 

„ 5- 37 


99 

4 

62.3 

„ 7-37 

” 


3 

65.9 

ii 

„ 8 — 37 



4 

72.7 

ii 

„ 9— 37 



3 

72.1 

Short 

„ 11-37 


Hybrid-Mexican 
Edith x D.C. 

4 

6 1.6 

Medium-long 

„ 12-37 

n 

Hybrid-Kristna 
Kata Kulu x No 79 

2 

71.1 

Medium 

„ 13—37 



2 

80.6 

Long 

„ 14-37 


ii 

2 

69.4 

Medium 

„ 15-37 

r, 

»i 

2 

82.4 

t* 

i, 16-37 



2 

75.9 


„ 17-37 

i, 


2 

89.8 

it 

„ 18 -37 


,, 

2 

73.1 

• 9 

„ 1<> — 37 



2 

82 (5 

tl 

.. 20-37 



2 

7(1,3 

1% 

21-37 

„ 

,i 

2 

56.1 


„ 22—37 

„ 

,, 

2 

64 8 


„ 23—37 

4 


2 

75 7 


24-37 



2 

47 9 

Medium long 

„ 26 -37 



2 

52 5 

Long 

26—37 



2 

56.5 

Medium-long 

27-37 



2 

57.1 j 

| Long 

„ 28 - 37 

1 , 


2 

68.1 

( Meilium-long 

29-37 

1 


2 , 

72 1 

, Medium-long 

„ 30-37 


1 

2 

65.1 

Long 

31—37 


i „ 

I 2 

• 67.5 

1 Medium-long 

„ 32-37 

No\r. 1937 

! Local .selection, 

l 

l • • » 

Medium 



Expt. Stn. 
G f town. 

i 

i 

1 


33-37 
„ 34—37 
„ 35-37 
„ 36- 37 
„ 37-37 
„ 3S— 37 1 

ii 

n 

" 

! « 

- ! 

ii 

i 1 

1 ;; 


1 

• • | 

# t9 

Medium- long 

„ 39-37 
„ 40-37 
„ 41-37 

i, 1 

ii i 

1 1 

i* 

ii 

ii 



• t 

Long 

» 41-37 

42-37 
„ 43-37 

ii 

ii 

ii 

ii 

ii 

ii 


••• 

i Medium-long 
Long 

ii 

44-37 

ii 

n 



„ 45-37 
„ 46-37 

ii 

ii 

„ i 

i !!! 

... 

ii 

n 

„ 47-37 

ii 

ii 



ii 

„ 48-37 





11 

„ 49-37 

ii 

Local selection, 
Expt, Station, 

i ::: 

i 


Medium-long 



Henrietta. 

; 



„ 50 -37 -> 

,, 5t — 37 

ii 

ii 

ii 

*i 

. • • 


ii 

Long 

ii 

„ 62-37 

ii 

i* 


... 

53-37 

1- ” 

ii 

. 

... 

n 



kBSULTS OF PAD I VARIETAL TRIALS. t )* 


Variety 

Date 

received. 

Origin, 

No, of 
seasons 
tested, 

Yield 
per 1000 
plants, 
lb. 

Type of Grain. 

No. 54—37 

Nov. 1937 

Local selection, 
Expt, Station, 
Henrietta, 


... 

Long, 

„ 55-37 



... 

... 

Medium-long. 

ii 

„ f>6— 37 





57 — 37 



... 

... 

11 

„ 58-37 


ii 



ii 

„ 59-37 


ji 

i 


ii 

„ 60-37 


n 

! | 


ii 

„ 61-37 


ii 



ii 

„ 62-37 


n 



ii 

Long. 

63-37 




j • • • 

„ €4-37 


i» 


1 

Medium-long, 

„ 65-37 

1 

ii 


| 

„ 66- 37 

1 

ii 


1 

Long. 

67-37 

i 

ii 



Medium-long. 

„ 68- 37 

1 

ii 



1 Long, 

69-37 

1 

1 

I 




i ii 


2. Henrietta Experiment Station. 


Blur Stir/, Variety * — Selections of this variety made from the 1930 
Autumn Crop were established in progeny rows during the 1937 Spring Crop. 
Four strains selected from these were put in a Strain trial (see page 86) with the 
ordinary Blur Stick , but results showed no significant difference in yield. 
Progeny Rows were still maintained in the 1937 Autumn Crop, and now there 
are under test twelve selections of this variety. 


Local hug grains . Because of the demand in Essequibo for long-grained 
types of padi, selection work was begun in the 1937 Spring Crop. Progeny rows 
of various padis were established, and now there are under test the following ; — 


Varieties Under Test at Henrietta Experiment Station. 


1 

Variet >’ rewived. 

No. of 

Origin. seasons 

tested. 

Type of Grain. 

LI 1936 

L2 

L3 < „ 

L4 

L5 1937 

L6 „ 

L7 

i 

Affiance 2 

Aberdeen 2 

Spring Garden 2 

Wakenaam 2 1 

Hampton Court ( — 

Johanna Cecilia 1 — 

L’Union — 

Long. 

Medium-long. 

ii 

... 

*4* 



98 


AGMCtfLttfRAL J&URltAL OP SftlTlStt GUlANA. 


‘[IX, 1 

Indian Padi. Daring the 1937 Antamn Crop progeny rows were establish- 
ed of a sample of padi received from Messrs. Seymour and Sayse Narayan, who 
imported it from India. The sample was very mixed, and before planting was 
arbitrarily divided into classes based on grain lengths. Selections were further 
made at the end of the crop, so that now there are 26 selections of this padi 
under test. 


PROGRAMME OF WORK FOR 1938. 

1. Variety Trials. 

Fourteen variety trials will be laid down in 1938 in selected sites of the 
Colony. These are as follows : — 

The first six trials will be carried out at Georgetown, Henrietta and Whim. 


A. Standard Long Grain Trials. 


I. 5 Randomised Blocks. 


II. 5 Randomised Blocks. 


1 . Padi Berbice 

2. D251 

3. D253 

4. D254 

5. D259 

6. Jaisingh 

7. Demerara Creole 

8. Kalyaman 

9. D114 \ 

10. D99 ) 


L. G. Controls. 


M. G. Controls. 


1 . 

2 . 

3. 

4. 

5. 

6 . 

7. 

8 . 

«). 

10 . 


D221 

Nickeric Patna 
Seymour S. 

No. 13-37 
No. 29-37 


D91 

Demerara Creole 
Kalyaman 


L. G. Controls. 


| M. G. Controls. 


B. Standard Medium Grain Controls. 


III. 5 Randomised Blocks. 

1. D94 

2. D108 

3. Unity 

4. D162 

5. D193 

6. D109 

7. Demerara Creole j L G Controlg . 

O* DmwI I 

10.' D99 4 ^ M - G - Coutr,,l8< 


IV. 5 Randomised Blocks. 

1. D258 

2. D261 

3. D262 

4. No. 15-37 

5. No. 16-37 

6. DUO 

7. Demerar, Creole j L „ C(ml „ ) | a . 

10.' M9 4 I M ' 0o “ lr<>U - 



RSsOlts of fAbi Varietal trials. 


9ft 


V. 5 Ramdomiscd 

1. D246 

2. D247 

3. D250 

4. D255 

5. D256 

6. D257 

7. D116 


Blocks. VI. 

1 . 
2 . 

3. 

4. 

5. 

6 . 

7. 

L. G. Controls. 

10 . 


8. Demerara Creole | 

9. D221 ) 

10. D114 ) 

11. D99 j 


M. G. Controls 


5 Randomised Blocks. 
No. 17-37 
No. 18-37 
No. 19-37 
No. 23-37 


Blue Stick. 

D115 

Demerara Creole J L G. Controls. 
]• M. G. Controls. 


The remaining trials are individual district trials and are distributed in the 
various localities mentioned. 


C. Individual District Trials. 


VII. No. 63 (Shied Trial) 

5 Randomised Blocks. 

1 . Demerara Creole 

2. No. 79 

3. D99 

4. D114 

5. D115 

6. D116 

7. Babylon No. 1 

8. Benab No. 1 

9. D97 (B) 

10. Benab No. 79 

IX. W. C. Berbice (site to be selected). 
5 Randomised Blocks. 

1. D114 

2. Demerara Creole 

3. Kalyaman 

4. D99 

5. No. 79 

6. D116 

7. D110 

8. D115 

9. D221 


VIII. W.C. Berbice (site to be selected). 
5 Randomised Blocks. 

1. Demerara Creole. 

2. No. 79 

3. D99 

4. D114 

5. D115 

6. D116 

7. Babylon No. 1 

8. Benab No. 1 

9. D97 (B) 

10. Benab No. 79. 

X. Henrietta. Long Grain 

XI. Trials with D114 as control. To 
be drawn up after results of 
Spring Crop. 

XII. Georgetown. Long Grain 

XIII. Trials With D114 as control: To 

be drawn up after results of 
Spring Crop. 



100 AGRICtri/rukAL JOUfeNAL Ofr BRITISH GttlANA. [iX, 2. 

XIY. Vreed-en-Hoop 

5 Randomised Blocks. 

1. D114 (control) 

2. D99 

3. DUO 

4. Kalyaman 

5. Demerara Creole 
tl. D115 

7. D116 

8. Seymour S. 

0. Jaisingh 

2. MISCELLANEOUS TRIALS. 

The trials to determine (1) the optimum age for transplanting seedlings 
(2) the optimum number of seedlings per hole have not as yet given any con- 
clusive results. Those trials will be continued at Henrietta during the 1938 
Autumn crop. 


3. DEMONSTRATIONS. 


In the districts certain varieties are being grown for demonstration pur- 
poses. These demonstrations can be seen in the named localities. 


District. 

Site. 

' 

Variety. 

", 

Area. 

W.C. Berbioe 

To bo selected 

Dm 

5 acres 


Abary District 

No. 7!) 

2 „ 

East Demerara 

No\ar. 

No 711 and 




D W 



Glazier’s Lust 

No. 79 

80 „ 


Co\e & John 

D114 

5 „ 

East Bank, Demerara. 

To be selected. 

D114 

U „ 


! 

No. 79 

1] „ 

West Demerara. 

La Grange. 

D114 

3 „ 


Fellowship. 

D114 



Vreed-cn-Hoop. 

D114 & 




DC. 

f» „ 

_ 

„ 

_ 



Manurial experiments are also being planned in conjunction with the 
Chemist and will be laid down both at the Georgetown and Henrietta Experi- 
ment Stations. 



THE VARIETY AND FERTILISER POSITION OF THE 
SUGAR INDUSTRY, IV. 

BY 

C. HOLMAN B. WILLIAMS, m.a., a.i.c.t.a., dip. agr„ 

Sugar Agronomist and Plant Breeder, 


ESTATE YIELDS IN 1937. 

The Department of Agriculture is again indebted to the Managers of the 
Colony’s sugar estates for kindly supplying statistics of the commercial yields 
secured during 1937. The date are condensed and presented in Table I. In 
Table II are given the weighted mean yields of the three principal varieties for 
the past four years. 

The outstanding conclusion to be drawn is the marked superiority of 
P.O.J. 2878 to its nearest rival, Diamond 10, on frontland soils. Large acreage 8 
of both canes have now been reaped, as plants, first and second ratoons, in several 
seasons and throughout the sugar belt, and it is clear that P.O.J. 2878 may be 
expected to yield, for a cycle of three crops, over a ton of sugar per acre more 
than Diamond 10. The latter is, however, a decided improvement on D. 025. 
On the pegasse soils, the differences are less marked, but P.O.J. 2878 continues 
to head the list. ‘‘Mixed ” areas, S.C. 12/4 and B.H. 10/12 should be eliminated. 

Table I. 

WEIGHTED MEAN YIELDS OF 96" SUGAR PER ENGLISH ACRE FROM THE MAJOR 
VARIETIES GROWN IN BRITISH GUIANA DURING 1937. 


Frontland Soils, Pkoasse soils. 




PO.J. 

2878 

Diamond 

I io 

D 625^ 

Mixed 

S.C. 

12/4 

i 

B.H. 

10/12 

P.O J. 
2878 

Wmond D 

Mixed 



1 Acre* 





, 




I 



Plant . 
( ’anes 

reaped • 

\ Yield ol 
HUgHr/acre. 

1,906.5 

j 6,908 7 

2.170.8 

i 

152.0 

3< 5.U 

67.1 

1,810.3 

*1.780.7 

343.7 

I , 

\ - 


VUmn 

3.811 

3.42 

XX 

2.04 

2.83 

* 3.40 1 

3.34 

3.20 

2,5)2 



FlTHt 1 
Rat- 4 

( AcreH 

2.227.2 | 








1 

! 


reaped 
Yield ot 


5.819.1 

4,008 1 

086.6 

240.2 

51.2 

001 6 

1,350 0 

1 66; « 

104.5 

221 

oons | 

1 MURnr/ucre. 
'-tons 

3 78| 

I 3.00 

2.97 

2.21 

2.85 

267 

3.10 

2.82 

1 2.70 

1 

2.03 

2.71 

Second 1 
Rat- 4 

f At*re<< 












reaped • 

1 Yield ot 

1,079.5 ( 

4.241-1.1 

(1,331.3 , 

1,018.2 

235.7 

18 h 

706 3 

832.3 

932.7 

407.3 | 

48.6 

oon» | 

HUgar/acre, 

'tons 

3.01 ! 

1 

3.23 | 

1 

2.02 1 

2.2C 

2.62 

2.36 

2.63 

2 44 

3.12 

2.0l! 

1.17 

Three 

'Total 


- 1 




j - 

— 

.J 

- 



— 

Yield of 


i 




j 






CropH 

RUgar/acre. 
.torn. : 

11.20 

i 

9 .05 

n. 12 ! 

7.14 

8.30 

8.43 

0 13 

8.55 1 

8.83 

4b 



i 



102 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 2. 


Table II. 

WEIGHTED MEAN YIELDS OF 96° SUGAR PER ENGLISH ACRE FROM THE MAJOR 
VARIETIES GROWN IN BRITISH GUIANA DURING 1934-1937. 




Frontland Soils. j 

Pegasse Soils. 



P.O.sl.2878 

[Diamond 10l D. 625 

P.O.J.2878 

Diamond 101 

IX 625 _ 

Plant I 

^ Acres reaped : 

8,707.4 

22,050.8 

24,654.5 

3,480 2 

l 

3,110.1 

2,525.4 

Canes j 

Yield of sugar 
i per acre, tons : 

i 

' 3.94 

355 

3.38 

325 

3.43 

3.51 

First 

j' Acres reaped : 

3,971.1 

17,082.4 

29,755.8 

1,818.3 

2,091.7 

3,7569 

Batoons ’ 

Yield of sugar 
^per acre, tons : 

3 76 

308 

l 

3.00 

3.16 

2.95 

2.81 

Second j 

^ Acres reaped : 

1,462.1 

11,418.1 

27,533.6 

860 6 

1,324.1 

3,373.5 

Batoons 1 

I Yield of sugar 






* 

i 

Iper acre, tons : 

3.25 

3 04 

2.67 

2.71 

2.46 

j 

2.70 

l 

[Total Yield of 







Three J 

sugar per acre, 




9 12 

1 

8.84 


Crops i 

.tons . 

10.95 

9.67 

i 

9 05 

9 02 


VARIETAL COMPOSITION OF THE 1938 HARVESTS. 

The estate Managers have also kindly furnished data from which it has been 
possible to prepare Tables III and IV and Figure I, showing the relative import- 
ance, by area, of the varieties to be harvested in 1938. 


Table III. 

PERCENTAGE DISTRIBUTION OF THE VARIETIES TO BE REAPED DURING 1938. 
( Varieties listed represent 100% oj the total area to he harvested.) 


Variety. 


Diamond 10 
P.O.J. 2878 
D. 625 
Mixed 
S.C. 12/4 
Miscellaneous 
B.H. 10 (12) 

\ 


Total English 
Acres in the 


^Percentage 
in West 


Percentage 

along 

Demerara 


(Percentage 
in East 


Colony. ) 

Demerara. 

River 

Banks. 

26,356.08 (41.3%) 

22.3 

39.3 

20,228.99 (31.7%) 

13.5 

6.8 

13,140.72 (20.6%) 

• • • 

2.6 

2,537.31 ( 4.0%) 

16.8 

44.5 

996.46 ( 1.6%) 

48.3 

43.1 

324 33 ( 0.5%) 

3.9 

34.4 

170.08 ( 0.3%) 
63,753.97 (100.%) 

73.3 

i 

9.5 


Demerara. 


17.1 
32.6 
34.9 

0.1 

1.2 

15.2 

17.2 


Percentage 

in 

Berbice. 


21.3 

47.1 

62.5 

38.6 
7.4 

46.5 



PLATE IV. 




WEST DEMERARA EAST DEMERARA 



Fig. I. 

Relative Varietal Composition of the Cane Areas to be harvested in British Guiana in 1938. 




Table IV. 


TfiB VARIETY AND FERTILISER POSITION OF THE SUGAR INDUSTRY, IV. 103 


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104 AGRICULTURAL JOURNAL OF BRITISH GUIANA. tlX, 2. 

The replacement of D. 625 by Diamond 10 and P.O.J. 2878 is progressing 
rapidly and only 21 per cent, of the acreage is now in the old favourite. On 
the other hand, P.O.J. 2878 is now expanding much more rapidly than Diamond 
19 and will probably soon pass it. “ Mixed ” areas continue to drop. These 
points are brought out in Table V. 

Table V. 

CoMPARIHOV OF AREAS OF D. 625, DIAMOND 10, P.O.J. 2878 AND “MIXED” 
IN THE COLONY DURING RECENT YEARS. 


Variety. 

Per Cent, of Total Area 

in the Colony. 

1934 | 

1935 

1936 i 

1937 

1938 

D. 625 

62.5 

55.4 

44.6 ! 

33.0 

20.6 

Diamond 10 

16.8 

22.7 

29.4 

36.6 

41.3 

P.O.J. 2878 

L4 

4.7 

9.7 1 

19.2 1 

31.7 

“Mixed” 

“ ! 

12.6 

12.7 

8.8 1 

4.0 


Diamond 10 and P.O.J. 2878 occupy 89 per cent, of the cane area in West 
Demerara and 85 per cent, on the Demerara River Banks, but in East Demerara 
and Berbice, D. 625 still covers 29 and 33 per cent., respectively, of the area to 
be harvested. 

The item “miscellaneous” includes mainly new seedlings which are being 
tested commercially. More areas could, with advantage, be devoted to thin 
purpose all over the Colony, but especially in West and East Demerara. 

FERTILISERS IK 1937. 

In Table VI, the fertiliser imports for 1937 are compared with those of 
recent years, the data being adapted from the Reports of the Comptroller of 
Customs. 



*hb Variety and Yertiuiser position of the sugar industry, iv. lflS 




106 


AGRlCULUfatAL JOURNAL OF BRITISH GUIANA. 


[IX, 2. 


Imports of sulphate of ammonia, which have shown a tendency to rise 
throughout the twelve-year period, reached a record of 11,171 tons In 1937. 
Its cost per ton has been climbing slightly since 1934. Imports of manurial 
lime (mainly pulverised limestone) were considerably higher than in 1936 and 
well above the twelve-year average ; its cost is dropping. Slightly less “ other 
fertilisers ” were imported than in 1936 and the cost per ton was a few cents 
lower. 

All the Bulphate of ammonia came from the United Kingdom and all of 
the manurial lime from the British West Indies (Trinidad and, to a lesser extent, 
Barbados). Of the phosphates, 77 per cent, came from Belgium, most of the 
rest from Holland and a small quantity from Germany. The potassic manures 
came almost exclusively from Germany. 

Of the money spent for fertilisers, some 77 per cent, goes for sulphate of 
ammonia, 15 per cent, for phosphates and potash, and 8 per cent, for limestone 
and lime. 

More than 95 per cent, of the fertilisers imported are used on the sugar 
estates and much of the remainder by small cane farm°rB. The estates have 
kindly supplied details as to the various manures used in 1937 and the data are 
summarised in Tables VII and VIII and Figure II. 

In 1937 the estates spent 79 per cent, of their fertiliser bill on sulphate 
of ammonia. The imports of lime have shown a further drop in favour of 
limestone which is easier to handle and cheaper. 





Fig. II. 

Relative Quantities and Values of Fertilisers used on British Guiana Sugar Estates in 1937* 



THE VARIETY AND FERTILISER POSITION OF THE SUGAR INDUSTRY, IV. 107 


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* [IX, 2# 



SELECTED ARTICLE 

EDTBLE COCONUT OIL* 

BY 

REGINALD CHILD, F.I.C., B.Sc\, pu.D. (Lorn) 

( Director of Research and Technological Chemist , 

Coconut Research Scheme ,) 

Refined coconut oil, either alone or in admixture with similar fats such as 
Palm Kernel and Babassu Fats, has been sold for edible purposes in Europe and 
elsewhere under a wide variety of trade or proprietary names. Among the best 
known of these (some of which are still protected by registration) are Cocolardo, 
Cocoline, Lactine, Laureol, Nucoline, Nutrex, Nutto, Palmine, Vegetaline and in 
India, Messrs. Tata’s well known Cocogem. As generic names for this type of 
edible fat have been used, Nut Lard, Vegetable Lard and Vegetable Butter. 

It has been pointed out that reference to these preparations as “ Vege- 
table Butters ” (and similarly in German “ Pflanzenbutter, ” and in French 
“ Beurro de coco ”) is unfortunate, since in temperate climates they are pure 
white, odourless and tasteless edible fats, which are not plastic and contain no 
milk constituents as do butter and margarine. In Ceylon and the tropics gener- 
ally coconut and similar oils are liquid and this point does not arise, since the 
word “ butter ” will not in auy case be applicable. 

The present article has been written since many inquiries have been received 
by the writer on the possibility of the local preparation and marketing of an 
edible grade of coconut oil. Some analytical figures obtained in connection with 
such inquiries are included. 

Standards of Edible Coconut Oil. 

Up to any point short of severe rancidity any coconut oil could in a sense be 
described as edible. Cheldiu oil, which may contain up' to 2 per cent, of free fatty 
acid and may bo of dark colour and strong odour, is consumed locally, but 
would by no means be reported by an analyst as of “edible grade”. Indeed for 
edible coconut oil used as such and in the manufacture of margarine, stringent 
standards have been laid down. For example a Committee of Analysts to the 
Ministry of Food in Great Britain in 1919 required “ fine ediblo coconut oil ” to 
contain less than 0.1 per cent, of free fatty acid (as lauric), not more than 0.5 
per cent, of moisture or 1 per cent, of unsaponifiable matter. The oil has also to 
be free from suspended impurities, and sweet and neutral in taste and odour. 
American authorities also lay down limits of colour; viz., not more than 12 
yellow and 2 red units on Lovibond’s Equivalent colour scale.t 

•Reprinted from the “ Tropical Agriculturist ” of Ceylon, Voi 89, No, 5, November 1937. 
tThis is net the same scale as referred to by the British Standard Specification, 



110 


AGBTCULTUBAL JOUBNAL OF BBIT18H GUIANA# 


[IX, 2. 


The oil further has, of course, to comply with standards laid down 
for coconut oil of any grade, <>.$., in the case of the British Standard 
Specification, the refractive index at 40°C. must be between 1*4485 
and 1.4492, and the iodine value between 7.0 and 9.5, whilst the saponification 
value should not be lower than 255. 

Commercially, oils of such high grade have almost always been subjected 
to processes of refining. 


Refining Processes. 

For the purposes of the present article it is unnecessary to give 
details of commercial refining processes, but it will be as well to mention 
the principles involved. It will be dear that to convert, say, a copra oil of 
ordinary mill grade to a refined oil meeting the specifications outlined above, 
four main stages of purification are necessary ; 

(a) Filtration or sedimentation to remove suspended impurities. 
Under this also may be included treatment to remove mucilagi- 
nous impurities which may escape removal by filtration. 

(b) Removal of free fatty acid by means of alkali treatment. 

(c) DeColorization. 

(dj Deodorization. 

Industrially, free fatty acid is almost always removed by means of caustic 
soda in slight excess ( about 0.2 per cent.) of the theoretical amount. After the 
soap so formed has been removed the oil is washed and dried, and the decolor- 
ization or bleaching treatment follows. This is effected by treatment with 
activated charcoal and/or fuller’s earth, folio sved by filtration* In the last stage 
the oil is treated in a vacuum apparatus with superheated steam which causes 
the odoriferous constituents to be distilled off. Technical details of this last 
operation are often strictly guarded as trade secrets. 

On an industrial Scale these opeiations require complicated plant and tech- 
nical control at all stages. Such plants do not, of course, exist in Ceylon and it 
is extremely doubtful whether any potential demand exists sufficient to encour- 
age anyone to invest capital in refining plants. 

Small Scale Refining. 

It is possible to refine a crude oil to a large extent by small scale methods. 
For example, the Department of Industries, Madras, has published a bulletin 
describing simple methods of refining oils, mostly devoted to describing the 
removal of free fatty acid by means of such alkaline reagents as lime, soda and 
silicate of soda. Bleaching with charcoal and/or bleaching earths can be adapted 
to a smkll scale and improvement of odour achieved, as is indeed done with 
CheJihu oil, by simple boiling with water. < 



EDIBLE COCONUT OIL. 


Ill 


Refining Losses. 

On such a small scale, however, refining losses are considerable. A. 1\ Lee 
of the India Refining Co., Philadelphia, published in 1924 an interesting 
account of coconut oil refining. The losses in refining an oil of f.f.a. (lauric) 
2.58 per cent, colour (Lovibond scale) 35.1 yellow, 5.85 red, to an oil of f.f.a, 
0.08 per cent., colour 4.01 yellow, 0.51 red, amounted to 6.1 per cent, of which 
5.5 per cent, was removed as acid oil for soap stock. On a small scale the losses 
are vastly in excess of this. 

Domestic Preparation of Oil in Ceylon. 

It is doubtful whether there is any necessity to attempt to give instruction 
in refining coconut oil to the local villager. When small quantities of a good oil 
are required they are prepared locally by the domestic method which will be 
familiar to local readers. 

The usual well-known proceduie is to grate the fresh kernels using the 
ordinary domestic scraper or hiramanai found in every Ceylon household. The 
grated meat with added water (about a pint to a nut) is hand squeezed and the 
resulting emulsion strained. A second squeezing after adding more water is 
usually given and even a third treatment by boiling with water and again 
squeezing. The emulsion of oil and water is boiled down until all the water is 
removed and clear oil is finally poured off from the caramelized residue. 

The oil yield is naturally low in comparison with that of commercial ex- 
pression of oil copra, and attempts to produce oil on a large scale by a modification 
of this process both in Ceylon and elsewhere have met with little success. An 
English Patent (No. 10,601/1914) claimed “ a process for the extraction of oil 
from the coconut and other nuts, consisting of reducing the kernel or flesh of the 
nuts to small pieces, adding water to about the bulk of the flesh and well mixing, 
subjecting the mixture to a process of grating, collecting the essential cream of 
the flesh produced thereby and laying the same on sieves and subjecting it to 
pressure to precipitate the essential cream of the flesh and water, Ac., Ac.” 
Plant is described for carrying out these and subsequent operations, which 
are seen to resemble closely the hand methods described above. This process 
does not appear to have been worked successfully. 

Parker and Prill in the Philippines in 1917 found that when freshly 
grated coconut meat was pressed at 1,000 lb. per square inch, over 60 per cent, 
of oil remained in the cake. By treating the material with water and steam 80 
per cent, of the oil could be obtained by pressing, it being found best to separ- 
ate the oil by chilling the emulsion to 60°F. 

< 

80 per cent, of the oil present seems to be about the best yield obtainable by 
hand pressing and it will be noticed that the domestic use of water and boiling 
to get further oil from second and third squeezings agrees with the results of 
Parker and Brill's scientific investigations. Six nuts are reckoned loyally to 
give a bottte of oil (about 670 gms.) and a trial under the writer’s supervision 



11? AGRICULTURAL JOURNAL OF BRITISH GUIANA, [IX* 2, 

gave from six nuts 760 gms., the nuts being of a size which would have given 
about 000 gms. of oil if converted into copra and hydraulically pressed, 

The oil obtained in this trial was yellow in colour, with a strong but sweet 
odour of the nut, and f.f.a. (lauric) 0.12 per cent. It is referred to as No. 4 in 
the table and the oil from a similiar trial as No. 3. Such oil is fairly satisfac* 
tory in keeping properties ; indeed the scientific literature contains some 
reference to it from this point of view. Lewkowitsch, for example, in his 
Standard work states that “ if the oil is prepared from fresh kernels by boil« 

ing (as is done on the Malabar coast and to some extent in Ceylon) it 

undergoes little change. ” 

Manufacture of Oil From Fresh Kernels Rapidly Dried. 

Since it is very unlikely to be economic to erect refineries in Ceylon, and 
since the domestic method of making an edible oil does not seem likely to be 
successfully adapted to a larger scale, the question arises whether any other 
method suggests itself for preparing coconut oil of edible grade without the 
necessity of refining. 

The only likely method, which has been tried twice on a fairly large scale 
is to disintegrate fresh kernels in the same way as is done in the preparation of 
desiccated coconut, but without removing the brown skin ; to dry the disinte- 
grated kernels in desiccators to the usual D.C. standard and at once to express the oil 
from the product*. The oils so obtained had the analytical characteristics given as 
Nos. 5 and C in the table. They were not completely odourless, though nearly so, 
and had a bland taste but otherwise would be regarded as up to the edible grade. 
For local sale it is possible that less stringent standards would be necessary as re- 
gards odour — a slight sweet odour and taste of coconut might not be objected to. 

This oil was sold at tho ordinary price of White Oil as there was no special 
demand for oil of a special grade in small parcels. Retail sale was not, however, 
attempted. 

Analytical Figures, Abnormal and Otherwise. 

The table of analyses summarises results obtained on various samples 
submitted by enquirers, some of whom have attempted small scale refining methods, 
and special methods ot preparation (of which the writer has not always been 
informed). Other figures lrom the literature are given for comparison. It will 
be noticed that some samples give abnormal figures for iodine and saponification 
values and for refractive index. In these cases it is not suspected that the sam- 
ples have been adulterated ; to obtain a waterwhite oil, the samples have in many 
of these instances been prepared from the white meat only. It is well known that 
“ paring ” oil obtained as a by-product in desiccated coconut manufacture has an 
average iodine value much higher than that of ordinary oil, a lower saponification 
value and density, and a higher refractive index. Correspondingly, oil from the 
white meat, or pressed from desiccated coconut, has a lower iodine value and 
refractive index, and a higher saponification value. 

Oifuz and West of the Philippines reported an analysis on white oil fron$ 
desiccated coconut, with the results shown as No. 10 in Table I, t 



tJDlBLfi COCONtrt 6IL, 


113 


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114 


AGRICULTURAL JOURNAl OF BRITISH GUIANA, 


[IX, 2. 


In the case of domestic oil the scraping stops somewhat short of including 
all the brown parings, so that these oils show iodine values slightly less than 
ordinary oil, but not so low as those from the white meat only. 

The percentage of unsaponifiable matter has not been determined on the 
samples reported here. At one time it appears that paraffin wax er heavy paraffin 
oil has been added to coconut fat (in temperate climates) to give it a consistency 
more resembling butter. The latter found in a sample of “ vegetable butter,” 
3.9 per cent, of unsaponifiable matter of iodine value 2.05, saponification value 
O, refractive index 1.475 at 4(UC. The writer has examined a similar paraffin 
oil, which, it was stated, was used as an addition to edible oils. This had iodine 
value 2.3, saponification value 0.2. refractive index 1.465 at 40°C. Such 
additions are unlikely in Ceylon ; to liquid oils there would be little point 
in them, and as mentioned above, they have not been looked for in local samples. 


Coconut “Stearin” and “Olein”. 

Edible coconut oils of various melting points are obtained by the process 
known as "winterising". By pressing the partly solidified oil at various 
temperatures it is separated into higher and lower melting portions, the pro- 
portions depending on the temperature and pressure. The higher melting 
portions are referred to as “ coconut stearin ” and the lower as “ coconut 
olein ”. The aqalytical constants of these will lie respectively on each side 
of the average values for ordinary oil. Bolton gives the following usual 
limits, but mentions that “ there are manufactured products made in a great 
variety of melting points, according to the extent of pressure, and only the very 
extreme figures are given, and practically all commercial samples yield figures 
well between these limits ”. 


' Coconut Stearin. Coconut Olein. 


Melting point °C. 
Incipient fusion 
Complete fusion 
Solidifying point °C. 
Saponification value 
Refractive Index 40°C 

Iodine Value (Wijs) 
Sp. gravity 1*9°/15°0 

F.f.a. (laoric) 
Reichert-Meissl value 
l’ol^pske value 


Usual 

Limits. 


20—31 

24—29 

252—235 

1.4483— 

1.4487 

2—7.9 

0.800— 

• 0.809 
0.2— 5.0 
4.5— 0.0 
8.0-15.0 


Typical 

specimen 

(refined). 


29 | 

30 I 

27.4 1 

252.1 

].448Cj 

4.1 

0.860 

0.1 

5.0 

10.7 


Usual 

Limits. 


10—22 
14-22 
257-262 
1.4492— 
1.1494 
1 1—15 
• • • 

3.13 

8.10 

17—20 


Typical 

specimen 

(refined). 


21 

23.5 

19.1 
258.3 

1.4493 

14.2 
0.870 

0.2 

9.2 

19 


•Approx, from Zeiss butyro-refractometer readings 



fcblBLE COCONUT OIL. 


115 

A. P. Lee gives interesting particulars of the working of this process 
and describes a large scale trial in which the oil as described above was kept be- 
tween 12.5 — 15.5°C. for 40 to 60 hours and then pressed, there being obtained 38.2 
per cent* of hard butter or stearin of solidifying point 26.68°C* and 00.95 per 
cent, of olein of S*l\ 20.3°(\ 

It will be apparent that some care has to be exercised in interpreting the 
analysis of edible coconut oils. Oils from the white meat only have low iodine 
values like “stearin,” but whereas the former tend to have saponification values 
above the average, the reverse is true of the latter. Similarly the iodine values 
of “olein” (above the average for ordinary oil) may approach those of commercial 
parings oil, but the latter have saponification values well below the average for 
ordinary oil, whilst 44 oleins ” are about the average or a little above. Coconut 
“stearin ” is more used indirectly for edible purposes than directly, as a 
substitute for cacao butter in chocolate and confectionery. 

Hydrogenation. 

Coconut oil can be hardened by the process of hydrogenation. The melting 
point can be raised to about 44.r»°C, when the iodine value is reduced to 1 0. 
The saponification value is not greatly altered. 

EcONOM 1 c C( >NS1 DER A T IONS, 

Whilst coconut oil hardened by hydrogenation and high melting coconut 
Stearin might be useful in the tropics as edible fats for cooking, etc., it is very 
unlikely that the processes for their manufacture could be economically worked 
in Coylon. Enquiries are occasionally received by the writer asking for details 
of such processes — particularly hydrogenation — to which the reply is generally 
made that the processes require extensive plant and expert technical management* 
and that there is little likelihood of their inception locally. 

It is said that whilst it is true that local demand would not justify an edible 
oil industry, there is a possibility of an export business. This is, in the writer’s 
opinion, also unlikely. Neighbouring countries are all themselves oil (and 
particularly coconut oil) producing countries. India in particular already 
protects her oil crushing industry by a heavier duty on oil than on copra. 
Many European and other countries w beie refining inteiests exist put a heavy 
tariff on edible grades of oil, whilst admitting unrefined oil at lesser rates. 

Any attempt at retailing edible oil in Ceylon is likely to remain a small- 
scale business, and the oil either prepared by the simpler method outlined, or 
refined by methods applicable on a small scale* 

Vitamins in Coconut oil. 

i 

Whilst there is some evidence that coconut oil in its fresh state contains 
Some vitamin A and vitamin 1‘i, it is not a good source of any vitamin, and 
vitamins are unlikely to be present at all in the refined oil. Home manufacturers 
therefore add vitamin preparations and a well-known proprietary brand in 



116 AGRICULTURAL JOURNAL OF BRITISH GUIANA. £lX, 1 

* 

India is stated to contain added vitamin D. Vitamin preparations can bo 
purchased from pharmaceutical houses, but their local preparation or use is not 
likely to become a possibility of interest, the object of health authorities being 
more to ensure that the local dietaries contain sufficient vitamins in other 
natural foodstuffs used. 

Addition of Flavouring Matters. 

Flavouring matters have been added to refined coconut and other oils. 

As recently as 1929 it was shown that the substance responsible for 
the aroma of butter is diacetyl. This has been added to margarine in small 
traces to imitate the odour of butter and its use in edible coconut and other fats 
has been tried. 

Other Modifications. 

Processes have been devised to render coconut fat plastic so as more to re- 
semble lard or butter in texture. The fat is submitted to processes of foaming 
with air or carbon dioxide and of kneading to the required consistency. These 
do not in the ordinary way apply to the tropics where the fats are liquid oils. 

Keeping Qualities. 

The oldor text-books on oils and fats used to mention coconut oil as one of 
the most susceptible to rancidity. This was true of the inferior copra oils 
formerly shipped, but as mentioned above oil prepared from fresh kernels or 
any oil initially sound keeps well, as do well refined oils, particularly in air- 
tight containers protecting the oil from light and air. 

The stringent standards laid down have the keeping quality of the oil in 
view as well as its initial soundness. 

The use of preservatives such as bensioic or chloroben/.oic acids or of anti- 
oxidants should not be necessary, particularly in an oil intended for quick local 
Consumption. 

Summary. 

The present article reviews the processes used commercially in the prepara- 
tion of coconut oil of edible grade, and mentions the modified forms under 
which such oil is marketed. From the local point of view the opinion is expressed 
that large-scale refining and other processes are unlikely to be worked in Ceylon, 
as there is Unlikely to be an extensive local demand and the possibilities of 
export are doubtful for tariff and other reasons. 

The preparation of coconut oil suitable for edible purposes locally on a 
smaller scale for retail marketing may be possible ; processes are suggested for 
producing an initially sound oil needing no refining, and mention made of the 
possibility of small-scale refining. 

Analytical reports on samples of various kinds examined in the writer’s 
laboratory are tabulated, and some figures from the literature given for com- 
parison, 



NOTES. 


Boron in Agriculture.— In Research Bulletin No. 5 (West of Scotland 
Agricultural College Plant Husbandry Dept.), R. W. G Dennis and 1). G. O’Brien 
draw attention to the part played by boron in agriculture. 

The interest in boron as a component of lield crops arose in 1910, when 
•Agulhon published results of Held tests, in which he obtained increase in dry 
weight of 50 per cent, for maize, 21 per cent, for colza, and 32 per cent, for 
turnips, as a result of applying 0.5 grammes of boron (as boric acid) per square 
metre. Yet there was no proof that boron is essential for plant growth until 
Brandenburg in 1931 demonstrated that boron deficiency occurs in the field, 
and is the underlying cause of dry-rot in sugar beet and mangolds. Boron 
almost immediately took its place in the list of accepted fertilizers. 

Boron in this Soil. 

Although boron is an essential component of some 5f> minerals, the majority 
of these are rare or of restricted occurrence, and the only widespread member 
of the group is tourmaline — a boro-silicate of aluminium and iron. It is doubt- 
ful, however, if t mrnuline forms a source of boron available as plant food, as it 
is resistant to weathering, but its occurrence in the Held in rocks or soils may 
he an indication that boron deficiency is unlikely in that area. On the other 
hand, tin' comparatively high boron content of sea water Jed to the suggestion 
that the boron content of soils and rocks is derived from the sea, and thus clay 
soils of marine origin are usually adequately supplied with this element. 

Boron Deficiency in Some Tropical Crops. 

Suf/ttr Symptoms of boron deficiency in sugar cane grown in 

water cultures have been described in detail by Martin, who employed cuttings 
of the Varieties 11 109, T.O..J 30, P.O.J. 2878, Yellow Caledonia and Badila, pre* 
viously rook'd in black volcanic sand. 

The most marked effect of boron deficiency was the retardation of growth, 
Usually, after one or two months the first definite symptoms developed as minute 
elongated watery spots on the young leaves. These lesions elongated parallel 
to the vascular bundles and resulted in a striping of the leaves. Older lesions 
exhibited p dark red centre surrounded by chlorotic tissue, and, finally, fracture 
of the dead tissue occurred. Young leaves w f ere short, narrowed at the base, 
and chlorotic, with irregular brown edges. The symptoms also included en- 
largement of the lower cells of the bundle sheath in the leaves, sometimes so 
marked as to cause the formation of elongated gall-like bodies on the lower leaf 
surface. The^ bundle fibres were poorly developed ahd lacked the normal silica 



118 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [l% k 

content. Martin remarks that the symptoms observed in his cultures very 
closely resemble those of Pokkah-boeng disease of sugar cane, associated with the 
fungus Fmarium moniliformc Sheldon, and suggests that the severity of this 
disease is related to the degree of boron deficiency in the sugar cane plant. 

Rice, In a series of pot cultures in a weakly aoid clay soil Tokuoka and 
Morooka showed that a concentration of 20 parts per million of boron was toxic 
to the plants. Larger quantities of boron led to extensive growth of Gladm- 
porium on leaves and grain. Later they reported that minute doses of boron 
increased the number of grain-bearing stems per plant and raised the yield of 
grain. Optimum growth was secured at a concentration of 0.4 parts per million 
of boron. They concluded that boron was not essential for the growth of rice, 
but did not determine the pre-existing boron content of the soil used. 

Citrus : Haas and his fellow- workers have shown that in sand culture, 
boron to the extent of 0.2 parts per million of the culture solution is essential 
for the normal growth of citrus. The deficiency symptoms are summarized^ as 
follows: “Leaves curled along the midrib with the tip of the leaf curling 
downward ; leaves coloured a brownish or yellowish green, often with a yellow- 
ing along the midrib; midrib or veins conspicuous, corky and split; and a pro- 
gressive loss of affected leaves in the basi petal direction. In severe cases there 
is a tendency towards “multiple bud ” formation due to new twigs dying when 
barely visible. When the bark of the internodes of the twigs, or in severe cases, 
that of the trunk, splits, au amber coloured gum oozes out. Eventually the 
cracks may widen so that the woody tissue is exposed. In severe cases the 
apical portion of the branch dies back. The roots become dark brown in colour 
and fail to elongate and in advanced cases the rootlets decay. On adding a 
suitable concentration of boron to the culture solution the symptoms of decline 
disappear”. 

Maize : The evidence so far available indicates that little advantage can 
be expected to accrue from the application of boron to maize. 

Tobacco t ]VrMurtrey found in water culture experiments that the 
effects of boron deficiency were usually apparent within a week or ten days of 
the transferring ot a plant to a nutrient solution lacking this element. The 
first visible effect was the manifestation of a light green colour of the leaves 
making up the bud, with the base of the individual leaf assuming a lighter 
green than the tip. When this appears, the bud has ceased to grow and has a 
Somewhat drawn appearance. This is followed in a day or so by the breakdown 
of the tissue at the base of the young leaves making up the bud. 

In the Deli district of Sumatra a disease called topziekte of tobacco occurs 
which corresponds for the most part with those of boron deficiency, and the 
addition of boric acid at the rate of 3 milligrammes per plant was effective in 
great% reducing the incidence of this disease. It was later found by Meurs that 
applications heavier than 6 milligrammes per plant would probably be toxic* 



KOTfiS. 


lii) 

in 1935 M’Murtrey described the occurrence of boron deficiency, as exemp- 
lified by the death of the terminal bud and crinkling of the upper leaves, in field 
plots laid down on sandy soil in Maryland, tJ.S.A. Boric acid was applied at the 
rate of 5 lbs. per acre and completely prevented further development of the 
disease. 

Cotton : By means of sand cultures carried out on a large scale in the 
open Eaton has shoun that boron is essential for the normal growth of cotton. 
Plants grown without sufficient boron became stunted, the leaves were buckled 
and irregular in shape, and most of the flower buds and young bolls were shed. 
A concentration of 1 part per million of boron was sufficient to suppress the 
marked deficiency symptoms, but the largest plants and greatest number of bolls 
were obtained with a nutrient solution containing 10 parts per million, although 
signs of toxicity were visible at this higher concentration. Analysis of the 
plants showed that boron is accumulated mainly in the leaves and Eaton estimat- 
ed that as much as 10 lbs. borax per acre per annum might be removed from 
the soil. 

Tomato * The symptoms of boron deficiency in tomato are death of the 
growing points of shoot and root with stimulation of development of secondary 
roots and axillary buds, together with thickening and curling of the leaves. 
Internal symptoms include brown discoloration of the cell walls, enlargement of 
the phloem, and deformation of some of the thin-walled tissues. The tissues of 
the flower stalk also degenerate and the flowers die prematurely. 

In Johnston and Fisher’s experiments, approximately four times as many 
fruits set on plants supplied with boron as on boron-free plants. On the latter 
the fruit were covered witn darkened or dead areas due to the breakdown of 
the cells. 

D.W.D* 


New Ornamental Plants introduced into the Botanic Gardens during 
1937. — The Gardens are much indebted to the Arnold Arboretum of Harvard 
University for a large selection of seed of ornamental plants, some of which 
yielded very welcome innovations. Besides a number of species of Aristolochia, 
which flowered in the Rockery and nearby, * there were several new shpubs, 
including Domheya Mastersii, and Strobilanthm isophylhu >*, which latter made 
a good showing opposite the bandstand and elicited several enquiries as to its 
identity. A smell Erythrina — E. Sencgalensis — bloomed profusely at the end of 
the year, and more plants of it have been set out. 

Apart from # the usual purchases of seed of annuals and perennials for the 
borders, and a few new rose plants, other introductions from seedsmen and 
nurseries included a large collection of dahlias from Holland, which attracted 
considerable attention when they were in bloom, a new species of Lonicera 
(L. TeUemanniana\ which has not yet been put out, and a pretty pale fhauve 
Achimenes which has flowered well in the Rockery* 



120 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [IX, t. 

A correspondent in Florida, with whom plants have been exchanged, sent 
us a good selection of Amaryllids, most of which however, have not yet matured 
gnffioiently to flower; one or two Amaryllids were also obtained from another 
correspondent in Sonth Africa. 

From Bermuda we received a new purple variety of Salvia, which flowered 
well in the borders, and has already found its way into some gardens in the 
town, a yellow Buddleia, which has yet to flower, and some Arum Lily seed. 

Some palm seed came to us from Porto Rico, and to another friend in 
Florida, we were much indebted for seed of an ornamental bamboo, Dendro- 
calamus at rictus. 

E. B. M. 


Legislation. — As a reminder to the public, attention was drawn in Depart- 
ment of Agriculture notice No. (>93 to new legislation introduced into Trinidad 
affecting the importation of plants. 

The importation into Trinidad of cacao plants and cacao beans from this 
Colony is prohibited. A certificate of origin stating that the following fruits 
and vegetables have been imported into British Guiana must be submitted before 
importation into Trinidad is allowed : pineapples, yams, sweet potatoes, tanniae, 
eddoes and dasheens. Plants, seed, cuttings and fruit of citrus, sugar-cane, 
bananas and cocmubs may be imported into Trinidad only if a permit from the 
Director of Agriculture of British Guiaua is obtained. 

An Order-in Council under Section .‘1 of the Plant Diseases and Peels 
(Prevention) Ordinance, 193.">, prohibits the importation into this Colony of 
Grapefruit from Trinidad and of all citrus fruit from the other islands of the 
British West Indies. 


British West Indies Fruit and Vegetable Councils —The first joint meeting 
nf the Eastern and Western Group Councils and the third meeting of the Eastern 
Group Council were held at the Imperial College of Tropical Agriculture, 
Trinidad, from February 9 to 15, I DBS. The chief recommendations are : — 

Recommendations. 

i. Grapefruit. 

Reoommondations 1 and 2 of the West Indian Intercolonial Fruit and 
Vegetable Conference (Jamaica) 191)3 relating to grapefruit and manges are 
endorsed by this meeting with the exception that it is recommended that future 
plantings of grapefruit should be restricted to the seedless varieties. 

It is also recommended that further extensions of grapefruit planting 
Sh&tld only be undertaken with caution and after careful consideration of the 
present world position. 



NOTES. 


m 


2. Mangoes. 

Recommendation No. 5 of the West Indian Intercolonial Fruit and Vegetable 
Conference (Jamaica) 1933 concerning mangoes is endorsed by this meeting but 
it is noted with regret that the absence of suitable and frequent shipping facilities 
among the Colonies of the Kastern Group makes development of a profitable 
trade problematical. It has also been noted that the Canadian market offers 
little prospect of development for this commodity. 

3. Avocado Pear a. 

This meeting while endorsing Recommendation No. fi of the West Indian 
Intercolonial Fruit and Vegetable Conference (Jamaica) 1933 concerning avocado 
pears desires to draw attention to the need for further experiments with West 
Indian and other varieties in order to provide the planting fublic with tjprs 
suitable for export. 

4. Pineapple*. 

This meeting endorses Recommendation No. 7 of the West Indian Inter- 
colonial Fruit and Vegetable Conference (Jamaica) 1933 concerning pineapples 
and finds that as there has been no improvement in the position regardiog either 
fresh or canned pineapples there appears to be no object in carrying ont 
extensive experimental work with this crop at present. 

5. Pooling of Information. 

The meeting has given consideration to Recommendation No. 10 of the 
West Indian Intercolonial Fruit and Vegetable Conference (Jamaica) 1933 con- 
cerning the pooling of information and finds that normally there is insufficient 
material for the regular publication of a bulletin of the type referred to in that 
Recommendation and considers that the Councils of the Eastern and Western 
Groups should arrange for the circulation of information as it becomes available. 

'fi. Marveling Intelligence Offirei . 

This meeting notes with satisfaction that the Eastern Group Trade 
Commissioner in Canada has undertaken many of the duties which would fall 
upon a marketing Intelligence Officer such as was suggested in Recommendation 
No. 1(1 of the 1933 Conference and that Jamaica has made an appointment of a 
development and Marketing Officer whose functions are of a similar nature. It 
is also noted that the Bermuda Government has established the necessary 
machinery for keeping in touch with Canadian markets. 

In these circumstances this meeting feels that the appointment of a whole- 
time West Indian Marketing Intelligence Officer in Canada is at present 
unnecessary but recommends that the closest contact should be maintained 
between the Eastern Group Trade Commissioner, the Marketing Division in 
Jamaica and the Department of Agriculture in Bermuda. . 

7. Oo-operation between citrus marketing organisations. 

This meeting having arranged a joint meeting between the Co-operative 
Citrus Growers’ Association of Trinidad and Tobago and the Dominica, Jamaica 



122 AGRICULTURAL JOURNAL OF BRITISH GUIANA, [IX, 2 

and British Honduras delegates recommends that the closest contact should 
be maintained in the future between the official citrus marketing bodies in 
Trinidad, Jamaica, Dominica and British Honduras with a view to the establish* 
ment at a later date of a West Indian Citrus Fruit Exchange. 

8. Re-establishment of an official agricultural department in Bahamas , 

This meeting records with satisfaction the efforts of the Bahamas towards 
the institution of more orderly methods of marketing tomatoes and suggests 
that it is desirable that estimates of acreage and production of this crop in the 
Bahamas should be made available as early as possible for the information and 
guidance of other producing Colonies. It is therefore hoped that the Govern- 
ment of the Bahamas will find it possible to re-establish the official agricultural 
department. 

9. Bananas . 

In view of the great importance of the banana as a cash crop in many of the 
Colonies of the Eastern Group this meeting recommends that every endeavour 
should be made to stimulate further production, 

10. Banana breeding . 

In view of the progress which has been made in breeding varieties immune 
to Panama disease and Cerrospora leaf spot this meeting strongly recommends 
that early steps be taken to provide the geneticists engaged in banana breeding 
with wild varieties of bananas necessary to serve as suitable parents for the pur- 
pose of breeding, as soon as possible, an immune variety with suitable commercial 
characters, • 

11. Low Temperature Research Stations . 

This meeting recommends that the officers of the Low Temperature Stations 
in Trinidad and Jamaica should collaborate in drawing up a schedule of optimum 
storage temperatures at which West Indian fruit and vegetables should be trans- 
ported and that this schedule should be revised when necessary in the light of 
further investigations. It is further recommended that the attention of shipping 
companies serving the West Indian area should be drawn to the necessity for 
adopting these temperatures as standards. 

12. Measures designed to control spread of Diaprepcs spp. 

This meeting recommends that all fruit, vegetables and ground provisions 
for export to Colonies where the weevils ( Diaprepes sppJ are not known to 
exist from any country or countries where the weevils (Diaprepes spp .) are 
known to exist must be accompanied by a certificate issued by a Government 
Inspector in the country of origin to the effect that the produce is reasonably 
free from foliage, trash and soil. 

13. The Anglo-United States and the Canada-United States Trade Agreements . 
This meeting desires to draw the attention of the Secretary of State for the 

Colonies and the Canadian Go verment to the serious effects on the British West 
Indian fruft and vegetable industries which have resulted from the Canada- 



HOTBS, 


123 


United Stated Trade Agreement. These effects have been most marked with 
citrus and miscellaneous vegetables other than tomatoes' 

It is noted with satisfaction that the continuation of the Canadian Preference 
on British Colonial tomatoes has been ensured through the Trade Agreement 
between the United Kingdom and Canada. A rednction or abolition of this 
preference would result in a serious setback to the tomato industries of the West 
Indian Colonies. The continuance of this preference is therefore essential. 

Through the abolition of the tariff on American oranges from January to 
April in each year the West Indian trade in this commodity has received a severe 
blow, since the peak of Jamaica production is in late December and January. 
An extension of the protected period for West Indian oranges in Canada to include 
the month of January is therefore most desirable and this additional month could 
be exchanged for an even longer period of free duty for American oranges in the 
summer months apparently without any present damage to Empire trade in the 
commodity. 

It is hoped to institute an advertising campaign in Canada for British West 
Indian limes, but with the existing ad valorem Intermediate and General 
Canadian tariffs on this commodity the West Indian Islands have little protection 
from foreign competition. It is therefore desirable that, in the interests of these 
Colonies, the Canadian Government be asked to amend the tariff on foreign 
limes to a specific duty of 2c. per lb. 

It is further recommended that the assistance of the Secretary of State for 
the Colonies be sought to represent the desirability of concession being given to 
West Indian limes and lime juice entering United States in the Anglo-United 
States Trade Agreement, negotiations for which are now proceeding. 

14 Empire preference on cifru* fnnt entering the United Kingdom. 

This Meeting having given consideration to reports of the possibility of the 
general rate of duty on citrus fruit on importation into the United Kingdcm 
being reduced, recommends that the attention of the Secretary of State for the 
Colonies be drawn to the disastrous effects which such action would have upon 
the growing British West Indies citrus industry which was developed "largely 
upon the recommendation of an expert who visited the West Indies in 1928 at 
the invitation of the Empire Marketing Board, a policy of development which 
was later confirmed by the Secretary of State following the receipt of the Report 
of the West Indian Intercolonial Fruit and Vegetable Conference convened by 
the Colonial, Office and held in Jamaica ip 1933 : the meeting further recom- 
mends that the Governor of Trinidad be asked to forward this recommendation to 
the Secretary of State for the Colonies by telegram and that the memorandum of 
the Trinidad Chamber of Commerce Inc. which is fully supported by representa- 
tives of all the British West Indian Colonies and the Jamaica Imperial Association 
be forwarded by airmail. 



134 AGRICtTfcmAL JOURHAt OP BRITISH OUUHA. tlX, 3, 

15* Preference* for British West Indian fruit and vegetables in Canada and 
the United States of America. 

This meeting views with regret that the abolition or reduction in Canadian 
preferences on West Indian vegetables has made trade in these commodities 
much more difficult and it is felt that the British West Indies have a fully 
Justifiable claim to consideration by the United States for concessions, even if 
seasonal and for a limited quantity, on vegetables, citrus and other fruits enter* 
hr* the United States in return for the concessions granted to the United States 
of America by Canada. 

The approaohing negotiations for an Anglo-American Trade Agreement 
offer a suitable opportunity for putting forward these claims, and it is hoped that 
the Secretary of State for the Colonies will arrange for the fullest representation 
on behalf of the British West Indies. 

16, Freight Bate 9, 

This meeting notes with alarm recent increases in freight rates which have 
been coincident in most instances with a reduction in commodity prices and 
desires to seek the assistance of the Secretary of State for the Colonies in watch- 
ing the interests of these Colonies in regard to freight rates. The meeting also 
hopes that Canadian National Steamships will maintain their sympathetic attitude 
towards producers in the West Indian Colonies and find it possible to remove the 
increases recently instituted in the Eastern group. 

17. lime Grower * Associations and a West Indian Limes Association, 

This meeting notes with satisfaction the successful foimation of a West 
Indian Lime Oil Sales Company and recommends that lime oil producers in 
Colonies not yet affiliated to that Company should give favourable consideration 
to such central marketing organizations. 

It is apparent that farther progress in the marketing of limes and lime 
products can only be satisfactorily developed and extra production allowed for 
by means of centralised advertising directed through a joint West Indian associa- 
tion of lime growers and other lime interests. This meeting therefore strongly 
recommends the early formation of Lime Growers Associations in all the West 
Indian Colonies concerned to be followed by tho formation of a West Indian 
Limes Association with the constitution recommended at the meeting of lime 
growers representatives held at the Imperial College of Tropical Agriculture on 
February 12th, lflfiN. 

This meeting farther recommends that this West Indian Association when 
formed should tuke steps to obtain the co-operation of lime interests in the 
Gold Coast. 

It is farther recommended that all West Indian lime producing Colonies 
should institute a system of export cesses or other contributions to provide funds 
for the West Indian Limes Association on the basis of fid. per lb. on distilled lime 
oil, Cd. per lb. on ecaelled lime oil, fid, per barrel on greon limes and Id. per gallon 
on top pulp juHe exported. 



NOTES. 


125 


This meeting also notes that Recommendation No. 3 of the West Indian 
Intercolonial Frnit and Vegetable Conference (Jamaica) 1933 relating to limes 
and lemons has not been followed by certain lime growers and while it does not 
appear practical to prohibit farther plantings yet it is felt that the dangers of 
over-prod notion are now more apparent than they were in 1933. 

18. Utilization of the services of the Colonial Marketing Board. 

This meeting strongly recommends that the possibilities shonld be explored 
of the means of utilising the services of the Colonial Marketing Hoard for the 
benefit of the Wc3t Indian fruit and vegetable industries, and that the collaboration 
of other bodies such as the West India Committee and the Canadian West Indian 
League should besought to work with the official marketing services in the Colonies 
as well as the two Croup Councils. 

This meeting farther recommends that the Commissioner of Agriculture, 
Imperial College of Tropical Agriculture, and the Development and Marketing 
Officer in Jamaica should be requested during their visit to the United Kingdom 
during the summer of 1 938, to seek the assistance of the Agricultural Adviser 
to the Secretary of State for the Colonies and the Colonial Marketing Board in 
regard to expanding the markets for limes and lime products. 

19. United action by Colonial Governments. 

This meeting recommends that the Governments of the Colonies represented 
at this meeting should unite in making representations to the Secretary of 8tate 
for the Colonies and other Governments on subjects of general importance relating 
to the frnit and vegetable industries although this should not preclude individual 
representations on matters more directly concerning a particular Colony. 

Organisation of Intercolonial Trade in Fruit and Veoktarles. 

Arising out of the discussion on various trade matters, the view was 
expressed by Professor Dash that the time had arrived for the careful investiga- 
tion of the Intercolonial trade in fruit and vegetables from the commercial as 
well as the quarantine aspects. The Conference fully endorsed this view. It 
was suggested that a Committee should be appointed to investigate conditions of 
the trade. The proposal is that each Colony should be asked to give an idea of 
the seasons of their main fruit and vegetables and the likely expoitable surpluses 
for intercolonial trade. Such information would form the basis of possible trade 
agreements between the various Colonies, with a view to preventing competition 
of looally-grown produce with imported commodities of a similar nature. By 
careful regulation periodic gluts would be avoided and better prices ensured to 
producers cs a,wholo. It would also help to make these Colonies self-supporting 
in regard to Caribbean grown fruit and vegetables. 



NEWS, 


His Excellency the Governor, accompanied by the Director of Agriculture, 
visited the economic farm unit at Toevlugt, West Bank, Demcrara, on Thursday, 
April 21. 

His Excellency also visited the Central Offices of the Department on 
Wednesday, Juno 15. 


Sir Geoffrey Evans, Principal, and Mr. E. McC. Callan, Lecturer in 
Entomology, of the Imperial College of Tropical Agriculture, visited the Colony 
with a party of post-graduate students from April G to 15. These tours have 
become a regular feature and enable students to obtain first hand knowledge of 
the Colony’s agricultural and forest industries and its economic problems. Such 
intercourse cannot but be of advantage to all concerned. 


Mr. G. Milne, M.Sc., F.I.C., Soil Chemist to the East African Research 
Station, Amani, visited the Colony from April 8 to 11). Advantage was taken 
of this visit to discuss the different aspects of the soil and agricultural problems 
of the Colony. 


Dr. D. S. Fernandes, Director of the Department of Agricultural Economics, 
Paramaribo, Suriname, paid a visit to the Department on April 19. It was a 
veiy welcome opportunity for exchanging views with Dr. Fernandes, especially in 
connection with the curing of Liberian coffee, a subject to which he has given 
considerable Btudy. 

Dr. Sant, Government Analyst, also of Paramaribo, visited the Department 
on May 13. 


Dr. A. C. Smith of the New York Botanic Gardens, who had accompanied 
the Terry-Holden expedition to British Guiana, visited the Botanical Division 
of this Department on May 13 and 16. Dr. Smith made a large collection of 
plants in the Rupununi District, specimens of which are being sent to Kew. 

Another visitor from New York was Judge Jacob Panken, who arrived on 
June 14. 

The Director of Agriculture was on tour in Berbice from March 28 to April 
1 and in Esseqfuibo from April 30 to May 4. 



NEWS, 


127 


Daring the period ander review the Deputy Director of Agriculture paid 
visits of inspection to Anna Begins, Leguan, the banana experiment and 
economic farm settlement on the West Coast Demerara and to rice areas on the 
West Coast Berbice and the Corentyne. 


The Botanist and Chemist visited the North West District, leaving George- 
town on April 2.1 and returning via Pomeroon on May i>. While in the district 
they inspected the Department’s station and sub-station at Hosororo and Wanna 
respectively and visited a number of the chief landholders and farmers, with 
whom they discussed various matters of agricultural interest. In addition, a 
number of small grants were visited. 


Major Thomas Bone, O.B.E., M.R.C.V.8., Government Veterinary Surgeon, 
left the Colony on 4 7/30 months leave prior to retiring. Major Bone joined 
this Department in 1028 after seeing army service in England, Ireland, France, 
India and Italy. After retiring from the army, the Major served for one year 
with the British South Africa Company, afterwards in Rhodesia, and became 
Chief Veterinary Officer to the Compania de Mozambique, Portueuese East 
Africa. He acted as Senior Veterinary Officer in South West Africa (Mandated 
Territory). Major Bone has served in British Guiana for about 10 years during 
which time a considerable enlargement in scope of the Department’s livestock 
investigations and activities has taken place, the benefits of which can only 
be fully felt as time goes on. Results are, however, already apparent in the 
case of dairy cattle, especially in the areas adjoining Georgetown. His col- 
leagues wish him every good fortune in his retirement. 


Mr. James I). Gillespie, B.Sc., Agricultural Superintendent in this Depart- 
ment from January, 1030, has been promoted to the post of Agricultural Officer, 
Sierra L**one. Mr. Gillespie is at present stationed in Berbice and will leave for 
his new post in August next. 


Officers of the Department who have already left or who will shortly be 
leaving the Colony on vacation are: Capt. F. Burnett, Deputy Director of 
Agriculture, L. D. Cloire, Entomologist, Major T. Bone, Government Veterinary 
Surgeon, C. H. B. Williams, Sugar Agronomist, H. E. H. Gadd, Rice Grading 
Officer, Miss V. Chan-Choong, Librarian. 

During the absence of Major Bone and Mr. Gadd, Mr. H. A. Fraser, B.V.Sc., 
and Mr. H. D. Huggins, Agricultural Superintendent, have been appointed to 
act as Government Veterinary Surgeon and Rice Grading Officer, respectively. 



.128 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX. 2. 

The Report of the Committee which was appointed to enquire into matters 
affecting the rice indnstry was published as Leg. Oo. Sessional Paper No. 1/1938. 
Mr. Percy W. King, Crown Solicitor, was Chairman, Oapt. F. Barnett, Deputy 
Chairman and Mr. H. E. H. Gadd, Secretary, 


His Excellency the Governor has been pleased to appoint a Committee to 
report on the advisability of establishing a central rice mill on the Esseqnibo 
Coast for the purpose of affording relief in that area. 


A meeting of the Board of Agriculture was held at the Head Office, Depart- 
ment of Agriculture, on March 21 and a meeting of the Sugar Experiment 
Stations’ Committee was held on June 13, 



PLANT AND SEED IMPORTAf 10^. 


Introdactions by the Department of Agriculture for the period 
March — May, 1938. 


Name 

Quantity. 

j Whence Supplied 

Economic. 




Asstd Vegetable Seed 

17i 02. 

H, 0. Hastings & Co., U.S.A. 

Cutting*, 12 cane varieties 

a 

of each 

Plant Quarantine S t a t i o il 
T rimdad. 

Derr is e! I i plica , 

1 

46 

cuttings 

St. Augustine Nursery, Trini- 
dad. 

Maize— I.C.M. 1 

3 

lb. 

I.C.T.A., Trinidad. 

I.C.M. 3 and 4 

2 

lb. each 

do. 

Mahogany Seeds ! 

4 

lb. ■ 

Dept, of Agriculture, Tiinidad, 

Nutmeg Seods 

500 


do. 

Soya Beau j 

1 

lb. 

I.C.T.A., Trinidad. 

Ornamental. 




Col villea mveinnm 

2 

OZ. 

Dept of Agriculture, Trinidad, 

Irctthtc ? er$choffeHu 

a 

plants 

do. 

iS 'air in far inured var. alba 

i 

pkt, sood 

do. 

BruvfeUia inti da 

Calfixtemon speeiaons 

I hi her ft a si hhoo 

Erf /I hrtna bevteronia na 

Lifsiloma sabian 

Veltophorum braMilieunr 

)■ 

pkt. i uch 

Secretary for Agric. Est avion 
Exptl. Agronomic », Cuba. 

Colnhiina Jerruginea 

3 

oz. 

do. 

Anthurium Lilies 

12 

plants 

Eden Flower Shop, Trin’.dad. 

Dahlias (asstd ) 

58 

bulbs 

Papcndroelit Vandervoet, Sas- 
senhoim, Holland. 

Boses 

4 

plants 

^ H. G. Hastings & go., U.S.A. 

ltoses (Double White Killarney) 

2 

plants 

i Peter Henderson & Co., New 
York, U.S.A. 

Swoot Bens 

6 

pkts. 

! do. 

Violet Tree | 

1 

pkt, 

j Mayaguez Expt. Stn., Puerto 
Hico. 





MEtEOfeOLOGICAL DATA— JANAURY TO MARCH, 1038. 


Rooording Sta ions & 
Months. 

Rain- 

fall. 

i 

j _ OS 

|JS 

1 

Botanic Gardens. 


January 

1334 

February 

1510 

March 

13.70 

Totals 

42.20 


Means 


Berbice Gardens, 


January 

February 

March 

10.55 

15.90 

15 G7 

-5 

Totals 

Means 

1 

42 21 

Onderneeming. 


January 

15 43 

February 

9-30 

March 

21 GO 

Totals 

4G f 2 

Means 

1 

Hoiororo, 

North West District 

| 


1 

January 

11- 43 

February 

10-25 

March 

14-03 

% 

Totals 

35-71 

Means I 

- 



fctfRR&frT HtCtS 6t COLONIAL PRODUCE 


From The Commercial Review , Journal of the Georgetown Chamber 
of Commerce , Vol. XXI , No. 5 , Tuesday , 31st May , 2955 . 

SUGAR. 

Per 100 lb. net 3 lb. per Bag allowed for tare 


Dark Crystals for Local Consumption 13.30 

Yellow Crystals do. do $4.00 

White Crystals $4.75 

Molasses Sugar none offering. 


Above Prices include Excise Tax of 90c. 

RUM. 

Imperial Gallon. Cask included. 

Coloured, in Puncheons — 40 to 42 O.P...(for export). ..60c.; Hhds. 52c., Barrels 77c 


White, in Hogsheads— 40 to 45 O.P...(for local consumption) 45 to 55c 

MOLASSES. 

Per Imperial Gallon. Naked. 

Yellow (firsts) 10c. 

Yellow (seconds) 5ic. 


RICE. 

Rice per Bag of 180 lb. gross. Brown Super $4.00 to $4.25 ; No. 1, $3.75— 

$3.90 ; Wh'te, Non? available. Lower Grades $3.25 — $3.65 as to quality 
Padi per Bag of 143 lb. gross, $1.20 as to quality. 


GENERAL. 

Gold, Raw,... average per oz. $26 to $27. 

Diamonds,— pro rata as to quality average per carat $10 to $11. 

Timber, Greenheart, (Lower grade measurements) . . .40c.- to 60c. per c. ft. ; 

for export 72c. to $1.00 per c. ft. 

do. Railroad Sleepers — (Mora) $l,fi8each. 

Greenheart Lumber $70 to $80 per 1,000 feet. 

Crab wood Lumber $60 to $75 per 1,000 feet. 

Shingles, Wallaba, 4 x 20 and 5 x 22 inches,.... $4.50 to $6.00 per M. 

Charcoal, Capped for shipment 72c. to 85c. per bag. 

Firewood $2.50 per ton. 

Coconuts... Selects, $9.00, oulls $6.00 per M... Copra $2.00 per 100 lbs. prime Copra. 

Balata Venezuelan, none. Local Sheet. ..36c.' to 38c. per lb. 

Cocoa M ....19c. to 19ic. „ „ 

Coffee ..4|c. to 5c. „ „ 


N.B.— Duty Payable on value at time of Importation and rate of exchange on day of 
arrival. 



m * , ^ . a 


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OF DAWN. 1 

in quiet confidence*— | 
and in the adherence | 

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true success. The Royal | 

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Bank offers to legiti- 1 


mate enterprise the | 

|SV Hyg^> s**~s§ 

a 

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experience have built fj 


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ROYAL BANK: 

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OF CANADA ; 

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I ELECTRIC MOTORS 

s ______ __________ ____________ • 

I ■■ ■ 

f ARE IN A CLASS BY THEMSELVES FOR DRIVING- j 

DRAINAGE PUMPS 

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| and other Machinery connected with Agriculture. § 

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] The Demerara Electric Company, Ltd. ! 

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Vet. IX, No. 3. 


September, 1938. 


The 

Agricultural Journal 

Of 

British Guiana 


PUBLISHBD BY 

' THE DEPARTMENT OF AGRICULTURE, 

GEORGETOWN, BRITISH GUIANA. 


Pric* 


•e 
• • 


ee 

•l 


6d. 




DEPARTMENT OF 'AGRICULTURE. 


ADMINISTRATION 


Director of Agriculture ... 

Deputy Director 

Clerical 

Senior Clerk 
Registrar of Banks 

Class III Clerks 


Probationers 


Librarian 

RESEARCH BRANCH. 

Botany and Plant Pathology 

Botanist— Plant Pathologist and Superintend- 
ent , Botanic Gardens : 

E. B. Martyn, B.A., A.I.C.T.A. 

Technical Assistant : 

N. Persaud 

Chemistry 

Chemist : 

D. W. Duthie, M.A., B.Sc., Ph.D., F.I.C. 
Assistant Chemist ; 

C. L. C. Bourne 

Entomology 

Entomologist : 

L. 1). Clear©, F.R. Ent. S. (on leave) 
Technical Assistant : 

O. Williams 

Rico 

Assistant Plant Breeder : 

P. A. Chan-Choong, B.Sc., A.I.C.T.A. 

Sugar 

(In co-operation with the Sugar Producers) 
Sugar Agronomist and Plant Breeder : 

C. H. B. Williams, M.A., AXG.T.A., Dip. 
Agr. (on leave) 

Laboratory Assistants : 

H. B. Singh 

A. V, Wan-Ping, Dip. Agr. 

Statistical Clwhx 
J, B. Bourne (on leave) 


... Prof. The Hon. J. Sydney Dash. 
B.Sc, (Agric.) 

••• £• Burnett, M.C., M.A. (on leave) 

E. M. Peterkin (acting) 

SUff. 

J. F. Irving, M.C. 

W. G. Delph 

A. A. Thorne 
Miss D. M. Terrill 

Miss M. Cheong 
P. 0. Jackson 
••• s 8. A. Adams 
Miss R. Delph 
' Miss S, Lord 

Miss Y. Chan-Choong (on leave) 

LIVESTOCK BRANCH 

Veterinary Surgeon : 

,T. Bone, O.B.E., M.R*C.V.S. (on leave) 

H A Fraser, B.V Sc. (acting) 

FIELD BRANCH 

Agricultural Superintendents'. 

Be rbice— (Vacant) 

Demerara, East— E.M. Peterkin 
Demerara, East Bank— H. D. Huggins, 
M.Sc., Dip. Agr. 

Demerara, West— E. G. Benson, B.Sc., 
A.I.C.T.A., Dip. Agr. 
Essequibo-A. A. Abraham 
Assistant Agricultural Superintendent: 

Berbioe— E. M. Morgan 
Agricultural Instructors : 

Botanic Gardens— H. A. Cole 

( C. C. Dowding, F.L.S., 
Demerara, East—] F.R.H.S. 

I G. L. Leitch (acting) 
Demerara, East Bank— I. Dewar (acting) 
Essequibo— A. W. Sears 
North West District— L. E. McKinnon 
Berbice— O. F. J. Chnraman, Dip. Agr. 
Agricultural Assistants: 

Demerara, East — J. Indrobeharry 
Berbice— H. B. France * 

Sugar 

Field Manager (Centred Station J 
C. Cameron 
Field Assistants : 

L. A. Forte 
B. A. McArthur 



branch 

Technical Assistant : 

D. D. Blackman 

/ - 

Meteorological {Assistant : 

' f.iUt- 


«ps mum . ps*b 

Grading Inspector: 

EL E. H. Gftdd (on leave) 

H. B. Huggins (acting) 

Technical A»si*tant» : * ‘ * 

V. A. Bovell (acting) 
ft. ft. Boss 


ADVISORY BOARD OF AGRICULTURE 

Director of Agriculture, Chairman, officio* 

Deputy Director of Agriculture, Vice-Chairman, eac q#eto. 

Hon. Peer Bacchus 

Hon. R. £. Brassipgton . fM ••• 

Hon. J. W Jackson 7 , 

Hon. F. J. Seaf ord, o*B.a 


Mr. 8. Andries 
n B. B. Hunter 
„ W. H. Richards 


Members 


SUGAR EXPERIMENT STATIONS COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 

Hon. M. B G. Austin, o.b.e. 

Mr. H F: Chapman (acting for Mr. G. M. Eccles)... 
„ J. C. Gibson «•> 

„ A. Munson ... ... ... 

„ R.R. Rhodes 

„ J. Bee * ... 


Georgetown 
Pin. Bath 
Pin. Port Mourant 
Pin. Uitvlugt 
Pin. Diamond 
Pin. Albion 


\ Representing 
I the Sugar 
• Industry 

i which wain* 
I tales the 
/ Statlees 


CO-OPERATIVE CREDIT 


Director of Agriculture, Chairman, ex-officio . 


Hon. J. W. Jackson 
Rev. A. 13. Dyett ... 
Mr. C. Farnum ... 

„ J. L. Wills ... 


BANKS’ BOARD. 


i 


Members 


DISTRICT AGRICULTURAL COMMITTEES 

EAST DEMERARA 

Director of- Agriculture, Chaiiman 
District Commissioner 


Deputy Director of Agriculture 
Hon. J. I. deAguiar - 


Hop. £. M. Walcott 
Mr. 8. Andries ... 

,, M. Ghani 
W. H. Richards 
„ J. E. Wills ... 


Members 


Director of Agriculture, Chairman 
District Commissioner 


Deputy Bltectof of Agriculture 
Hon. J. W. Jackson 
Dr. the Hon. J. B. Singh 
Mr. R. P. Carryl * ... 

J.C. DaSilva • 

„ ILkB. Hunter .1. 

„ A. Murison ... 

„ W. Ramdeholl ..* 

„ A. Bayman ... 


WEST 



' «.t 


DEMERARA 



Members 


CONTENTS. 

(VOL. IX, No. 3.) 


Page 

EDITORIAL— 133 

ORIGINAL ARTICLES. 

Malaria in British Gaiana, 

Part II. ... . Q. (jrighoh. M D. (If.), M R.C.P. ( Land .), 

D.T.M. <1 R. (Eng.) ... ... 135 

Coconnt Wilt in Esseqnibo 

and Pomeroon Districts ... T). IF. Duthie, Ph.D , I.I.O. ... 147 

A Grade Dairy Herd ... H. A, Fraser, B.V.Sc. ... ... 153 

A Milling Test on Sixty 

Padi Varieties ... ... I). IF. Duthie, Ph.D., F.IC. and 

C. L. (\ Bourne. ... ... 163 

SELECTED ARTICLE. 

The Cultivation of Cajanus 
Cajan and the methods of 

* preparing marketable Dhal ... P. M. Gaywala, M.Ag. ... ... 169 

REPORT. 

Fifteenth Meeting of Advisory 

Board of Agriculture ... ... ... ... ... 178 

NOTE. 

Padi and Rice Production 

in India and Burma ... ... ... ... ... 183 

NEWS , ... ... ... ... ... 190 

PLANT AND SEED IMPORTATION ... ... ... 191 

METEOROLOGICAL DATA 

CURRENT PRICES OF COLONIAL PRODUCE ... ... 193 



Contents— Continued. 


ILLUSTRATIONS 


Facing Pag® 


Plat® 

I.— Fig. 

4 — Random sample of A. darlingi captured 
in houses in the Tillage of Rampoor, 
(Blairmont). 

144 

Plate 

II. — Fig. 

5 — Random sample of A. albitarsis caught 
in houses in the same village. 

145 

Plat® 

III. — Fig. 

1— “ Orchard Leigh Heilborn Mercedes.” A 
purebred Holstein Friesian Bull owned 
by the Department of Agriculture. 

156 

♦♦ 

,,-Fig. 

2— “ Candies Carbine.” A purebred Guern- 
sey Bull owned by the Department of 
Agriculture. 

156 

Plate 

IV. — Fig. 

3— A Grade Holstein-Creole Herd. ... 

157 

»» 

,, —Fig. 

4— Grade Holstein-Creole Calves, 10-12 
months old, reared on a commercial 
calf meal feed. 

137 

Plate 

V.-Fig. 

1— Apparatus for Steaming Padi. 

164 

Plate 

VI.— Fig. 

2 — Experimental Mill. ... ... 

166 

Plate 

VII.— Fig. 

3 — Close View of Grader, ... 

168 



The 

Agricnkoral Journal of British Guiana. 

September, 1938. 

EDITORIAL* 

ECONOMIC STOCK-RAISING. 

In a report on a visit to Palestine and the Trans-Jordan, the Agricultural 
Adviser to the Secretary of State for the Colonies pointed out that 44 the improve- 
ment of flocks is unlikely to be permanent until attention is given to feeding, 

for it has now been recognised that the class of animals which a country possesses 
depends upon the class of feeding which is provided.” This statement expresses 
concisely what is now accepted as a universal truth. It is being shown beyond 
question that the limiting factor to bigger and better livestock industries in 
British Guiana is the problem of cheap, balanced feeds. Thus, in the case of 
cattle in this Colony, the grazing in general is relatively poor and the pasturage 
is seldom regarded as a crop requiring drainage, cultivation, irrigation and the 
application of fertilisers ; but the cattle-owner cannot be too severely censured 
for this since the land on which his cattle graze is seldom his. Most of the 
lands rented for pasturage are grazed on the communal basis, and there has thus 
been in consequence little inducement for the individual to undertake the 
necessary expenditure for fencing and paddocking. Without fences and 
paddocks good pastures become poor and poor pastures become poorer. 

The significance of this pasturage problem in regard to the development of 
a cattle industry has been receiving much attention by the Department's Live- 
stock and other Divisions ; the feeding value of the Colony’s herbage has been 
studied on the Government Stock Farm and elsewhere, and it has been found 
that for the most part our fodders are deficient in lime and phosphate, but, in 
individual cases, contain considerable quantities of these constituents; by 
Judicious admixture nutritive and palatable feeds are being obtained. Some of 
the fodders used in these trials and giving promising results, include Demerara 
Primrose, Guinea grass, Para grass, Wynne grasS, Guatemala grass, Horse 
Weed, Teosinte and Iruhgofera endecaphylla. 

In an article in this number (“A Grade Dairy Herd”), are disof&sed the 
problems which are being faced in building up a dairy herd of good stock and 
maintaining satisfactory production in regard to quality and quantity. This 
herd has been run on a purely commercial basis and the passages on 44 Feeding- 
Staffs” and 44 Pastures” will well repay attention. 

The points, which thus far have been taken, are discussed both to show the 
dependence'of our biggest livestock industry — cattle— on the supply of suitable 
feeds and to indicate some of the steps which are being taken to achieve 
improvement ; but it is not only in the cattle industry that feeds play this 
dominating part. The same holds good for poultry, and in this industry much 
importance is attached to this aspect ; thus, when recently a series of meetings 
was held 4o consider the organising of a bigger local poultry industry, the ease 
for balanced rations at cheaper prices was given an early hearing. At one of these 
meetings, convened by the Director of Agriculture on September 5, the chief 
item discussed was the formation of a Poultry Association together with the aims 



134 AGRIC0 1/f tTB AL JOVBlXkt, Ot URttlSfi GtttAlU, [iX* 3. 

and policy of snob an Association. Now that the air hi clearing in respect to 
local agricultural industries, sugar, rice, livestock, and with the increased 
activities of Government in connection with importations of improved types* 
there is a growing trade in live poultry and eggs. Encouragement in this 
direction is being provided by recently improved steamer connections 
between Berbice ports and Trinidad so that shipments are now being made 
from Berbice and other ports of the Colony to that market. For these reasons 
it seemed desirable to organise an Association of some type which conld, in 
collaboration with the Department of Agriculture, exercise a watching brief over 
the industry, consider its needs, and undertake measures calculated to be of 
benefit to the movement generaJly. 

It is accepted that, because of a number of factors such as the high cost of 
feed, the low prices of eggs and poultry, and the absence of an outlet for surplus 
production, poultry activities have in the past been somewhat fitful. Of these 
factors the most important is the absence of a locally produoed and sufficiently 
cheap, balanced ration. Progress has, however, been made within recent years 
since it is now possible to import into the Colony, free of duty, certain feeds high 
in protein content. It is understood that the Demerara Meat Company which 
slaughters a good deal of the stock for consumption in Georgetown has in process 
of erection equipment suitable for turning out a cheap xfetioa high in animal 
protein and processed from blood and animal refuse. Feeds of the starchy type 
can be obtained iii abundance locally ; coconut by-products can be useful. 
In a country such as British Guiana, where rice is extensively grown, it would 
appear reasonable that by-products from this crop should be available to form 
the basis of a good ration. Up to the present, however, the rice milling systems 
which are in operation have, in general, found it difficult or impossible to recover 
the valuable rice by-products (e.g., rice bran, etc,,) and to make them available 
for animal consumption. Plans are now under consideration for the establish- 
ment of modem rice milling units. Apart from the direct benefit to the rice 
producers, centralized up-to-date mills will be able to separate by-products which 
will then be available in such quantity and quality as to make the outlook for all 
forms of stock more favourable. 

Another aspect of the feeding question will be a more general cultivation 
of peas and beans for use in poultry feeds ; these are rich in proteins and 
although farmers have in recent years undertaken the cultivation of blackeye 
peas on a much more extensive scale, much can yet be done. Appreciation of 
the fact by farmers that peas and beans might, in addition to cash sales, be 
converted into poultry and eggs and sold as such, should serve as a further 
inducement for the inclusion of more of these crops in the regular farming 
routine. 

An important factor which should be considered by those going into 
poultry-keeping as a business is whether or not the size of the enterprise 
embarked upon is large enough. Work done in many poultry-rearing districts 
has consistently shown that an influence of considerable importance in deter* 
mining raofit or loss in the poultry business is whether or not the minimum 
number 61 birds is being kept. When the number of birds kept is too small* 
the cost of supervisiotii feed, and sanitation make profits difficult if not 
impossible. 

With a better outlook for feeds and with the organisation of an active 
poultry msoeiation, the possibilities are brighter for building up poultry-rearing 
into a minor but promising industry. 



ORIGINAL ARTICLES. 

MALARIA IN BRITISH GUIANA. 

PART II. WHICH OF THE LOCAL ANOPHELINE SPECIES ARE 
RESPONSIBLE FOR THE TRANSMISSION OF MALARIA ? 

BY 

G. GIGLIOLI, m.d. (It.), m.r.c.p., (Lord.) ; d.t.m. & h. (Eng.). 

Medical Adviser to the Sugar Estates of British Guiana. 

We have seen that three species of Anopheles, A. tarsbnaculatus, JL albi- 
tarsis and A. darling i, exist in this Colony in large numbers and with a wide 
distribution. 

All of these are known as malarial vectors in other regions of Tropical 
America : A. tarsi inaculat us is a carrier in Panama and Trinidad : Kumm 
(1932) at Bahia, in Brasil, found A . albitarsis abundant in houses and 5.8% were 
infected with malaria; A. darling / is now recognized as the principal and 
most dangerous carrier in Brazil, from the Atlantic to the Andes, throughout 
the Amazon basin and in Venezuela ; more recently, it has been found in French 
Guiana. 

All these three species are susceptible to infection when made to feed on 
suitable malaria patients. We have ourselves had no difficulty in producing such 
artificial infeetions. These experiments are by no means conclusive as 
incriminating evidence, as the conditions which are created in the laboratory do 
not necessarily subsist iu nature. 

In the present section we propose to lead what evidence we have been able 
to collect concerning the relative importance of each ohe of these mosquitoes in 
relation to the transmission of malaria in this Colony. 

(I) Geographical and Topographical Distribution op Malaria 
in thk Colony, and its Relation to the Distribution 
op the Various Anophelinb Species. 

There is, no part of the Colony, on the coast or in the interior, which can 
be said to be entirely free from malaria. Concerning the incidence and the 
distribution of this disease it is necessary to bear constantly in mind that 
malaria infection can remain latent for weeks and months. The infection may 
not become apparent till long after the patient has left the locality where he 
contracted it. We have known cases which suffered their first attack in Europe 
several moifths after leaving the Colony. 




MALARIA IN BRITISH GUIANA, 


137 


The occurrence of & few cases of malaria in any one given place, therefore, 
by no means implies that the disease was acquired on the spot and that the 
locality must be regarded as malarial. 

In this connection the frequent displacement of the population from one 
district to the other, in search of work, must be considered. The gold, diamond, 
bauxite and timber industries keep a constant flow of men between the coast 
and the highly malarial districts of the interior. Cane cutting and rice planting 
and reaping again cause frequent seasonal displacements of the population along 
the coast and on the smaller rivers (Mahaica, Mahaicony, Abary and Canje). 

Apart from these well defined, regular and, more or less, constant or 
seasonal currents, one must not forget the ordinary displacement due to business 
or pleasure as, for instance, the prevailing custom, amongst East Indian women 
and children in particular, of “ passing time ” with relations or friends on other 
estates or in villages. * 

We will now outline briefly the methods currently employed for measuring 
the incidence of malaria. 

The Parasite index of a locality or community is given by the percentage 
of children, under 12 years, habitually residing in that locality, which actually 
harbour malaria parasites in their blood. This is a direct method of measure- 
ment giving exact data on the actual rate of infection at the time of the survey. 
Recent and acute infections naturally are the most easily detected. 

The Spleen index shows the percentage of children which present enlarge- 
ment of the spleen. This is a very frequent symptom of long standing and 
repeated malaria infection ; other diseases may cause the spleen to enlarge, but 
in this Colony such conditions are so few And rare that their influence may be 
overlooked. The splenic index, being affected mainly by chronic a nd repeated 
infections,. supplies information more particularly as to the habitual incidence of 
malaria in the locality. 

It will be noted, therefore, that the Parasite and Spleen indices give some- 
what different information ; by their comparison we are enabled to date the 
local malarial outbreak and to decide whether we are in the presence of recent, 
epidemic or acute malaria or of old standing, habitual, endemic or hyperendemio 
malaria. 

If malaria has only occurred recently, in epidemic form, many ohildren 
will be found with parasites in their blood, but their jjgleen, in most cases, will 
be only slightly if at all affected. The parasite inallt, therefore, is relatively 
'high whilst the spleen index, is low. Conversely if malaria has prevailed in 
the district for long years parasites and enlarged spleens will both be prevalent, 

. and the spleen and parasite indices will, more or lessf Coincide. These points 
-are well shown in diagram No. 1. 



138 


AQBICTTLTtrBAX JOURNAL 07 BRITISH GUIANA. 


[IX, 3. 


In the comparative study of spleen rates, in this Colony, it is very import- 
ant to give fall consideration to the racial factor. Negroes, though equally 
susceptible to malaria as other raoes, tolerate the infection better, and react lea* 
frequently and less conspicuously with splenic enlargement. In communities 
where Negroes abound the spleen index alone may give misleading results ; it 
should always be supplemented by the parasite index. Diagram No. 2 dearly 
illustrates this point. 

Between 1933 and 1937 we carried out repeated malarial surveys at Blair* 
moot and Providence on the Berbice River estuary, and at Bath on the West 
coast of Berbice. In 1937-38 we extended this survey to fifteen other estates 
from De Klnderen, on the West Coast of Demerara, to Skeldon on the Corentyne 
estuary. During the latter survey 5,814 children were examined for enlarge- 
ment of the spleen and from 2,389 blood slides were taken for the demonstra- 
tion of malaria parasites. Haemoglobin percentage estimations were also taken 
from each child, in order to determine the incidence and degree of anaemia. 

These surveys have shown malaria to be endemic or even hyperendemic 
along the West and East Coasts of Demerara, and on the Demerara and Berbice 
river estuaries, with a tendency to become less prevalent on the coast as we 
proceed towards the east. 

At Bath, on the West Coast of Berbice, locally aoquired malaria is definite- 
ly uncommon. In our last survey in 1937, the spleen rate was only 1.3% and 
the parasite rate 3.5%. On the Corentyne Coast malaria, under normal climatic 
conditions, is even less common. 

The last two years (1937 and 1938) have been definitely abnormal as 
regards malaria incidence. Between August and November, the disease prevailed 
in localities which are usually only mildly malarial ; malaria also became 
relatively common on the Corentyne Coast where, as a rule, it is absent. 

Our survey, during this period, yielded some interesting figures : 

At Albion, with a spleen rate of only 0.1% we found that 19.2% of children 
harboured malaria parasites (1937). 

At Port Mourant the spleen rate was 0.3% and the parasite rate 13.5%. 

At Skeldon 2% and 20.8% respectively. 

These remarkable discrepancies between the spleen and parasite rates, as 
has already been stated, indicate that malaria is not endemic on the Corentyne 
Coast. Its relatively high incidence, in 1937, must be regarded as a purely 
epidemic and, therefore, transitory occurrence. We will return to this subject 
later when dealing with the seasonal incidence and local epidemiology of the 
disease. ^ 

In the settled areas of the interior, on the Demerara, Berbice, lower 
Essequebo, Pomeroon and other tidal rivers, malaria is endemic and, in many 




-In the presence of chronic or repealed malaria infection the splenic 
negro child is very much leas marked than in the Eaat Indian. ^ w vn e 

t rates conditions on an estate on the West Bank, Demerara ; one soleen 

there is clear similarity between the parasite rates of the two raceB, the gr p 
rate is less than i of that of the East Indians. 


In negro communities, therefore, the spleen rate is of relatively little value ; it 
should always be supplemented by the parasite rate. 



140 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 3. 


localities, hyperendemic. Its occurrence in tbe upper reaches of these rivers 
is notorious ; such localities as the Potaro district and Kurupukari, on the upper 
Essequebo, have particularly bad reputations. The Rnpununi savannahs, 
formerly regarded as healthy, are reported to have suffered severely of late 
years. 

This brief review confirms our previous statement that in the Colony 
malaria is ubiquitous, but its incidence varies within wide limits. Roughly we 
may say that this disease is hyperendemic or endemic throughout the permanent- 
ly or temporarily settled areas of the interior ; on the estuaries of the great 
rivers and on the West and East Coasts of Demerara. 

On the front lands of the coast of Western Berbice it is very much less 
common ; on the Corentyne Coast proper there is no endemic malaria, but 
epidemic outbreaks recur at intervals. On the wide estuary of the Corentyne 
malaria of late years, has been very mild, but during the last twelve months a 
severe exacerbation has been noted. 

What correlation exists, if any, between thin peculiar distribution of Malaria 
and that of the three prevailing Anopheline U/teeies ' 

A. tarsinianila/as is only occasionally found in the forest areas of the 
interior, in localities from which the bush has been cleared. This low incidence 
is evidently and grossly disproportionate to the very high incidence of malaria 
in these districts. On the coast this species is abundant everywhere ; we have 
found it particularly prevalent in mildly or non-malarial localities on the 
Western Berbice and Corentyne coasts. 

A. albitarsis is eminently a savannah mosquito. We have not found it 
along the highly malarial tidal and flood rivers of the interior. It abounds 
throughout the East and West Coasts of Demerara, in pastures and rice fields ; 
it occurs in exceptionally large numbers on the backdams of Western Berbice 
estates and on the Abary savannahs. It is very common at Bath where malaria 
is only very mildly endemic. So far we have few data concerning this species 
on the Corentyne Coast but we had no difficulty in finding it at Skeldon, where 
it is very prevalent in the cane cultivation aback. We have also found it in cow 
and sheep-sheds at Industry on the Corentyne front lands, some 12 miles East 
of New Amsterdam. 

In our collection from the savannahs of the Rupuuuni this species accounts 
for A of the specimens. The periodic occurrence of mosquitoes in myriads 
during and after the rains has always been a well known feature of these 
savannahs. Myers established that these mosquitoes were all Anopheles ; but he 
failed ^o determine their specific identity. From these and our own findings 
w,e would conclude that during the wet season A. albi tarsia is exceptionally 
abundant on the Rupununi, and that it was equally abundant a few years back, 
when the savannahs were rsgarded as free from indigenous malaria. • 



MALARIA nr BRITISH GUIANA. 


141 


We are, therefore, led to conclude that the geographical distribution of 
4. tarsimaculatus and 4. albitarsis in the Colony does not coincide with that 
of malaria. Both these species are rare or absent where malaria is at its worst 
and conversely they abound habitually where endemic malaria is low or even 
absent. 

The geographical distribution of A. darlingi on the contrary coincides 
rigorously with the local distribution of malaria, moreover the incidence of 
malaria is directly proportionate to the incidence of this mosquito. 

Where 4. darlingi abounds malaria is hyperendemic ; where it is found 
habitually but in smaller numbers or only at certain seasons, malaria is endemic 
and seasonal ; where it occurs occasionally endemic malaria is absent but 
occasional epidemics follow in its train. 

Of the three species of Anopheles we are investigating 4. darlingi is the 
only one which is prevalent and wide-spread in the forest areas of the interior. 
It is very prevalent on the heavily infected river estuaries, and on the West and 
East Coasts of Demerara ; it is, at present, very abundant on the West Bank of 
the Corentyne estuary where an epidemic of malaria appeared in August last 
year, and still persists. 

This Anopheles is represented in our Rupununi collection. At Bath, in 
Western Berbice, where malaria is very mild, this species occurs but is rare. 
Of 669 Anopheles captured on this estate in 2 years, only 56 belong to this 
species. (,) 

On the Corentyne coast 4. darlingi is usually absent, but we found it 
present in small numbers at Port Mourant in October 1937, when a small 
epidemic outbreak was active. An epidemic is at present active at Albion ; we 
visited this estate on the 5th of September, and found 4. darlingi abundant in 
the houses. 

Even on individual sugar estates, studying the incidence of 4. darlingi in 
different yards and houses, in parallel with the malarial parasite and spleen rates, 
one is inevitably led to conclude that not only the geographical, but also the 
topographical distribution of this particular Anopheline species and that of 
malaria strictly coincide. 


( 1 1 In August this year, sinoo the present section was written, an epidemic outbreak of 
Malaria of some seventy has occurred at Bath. The spleen rate has risen from 1.5% in 1937 to 
20% and tbe parapite rate from h.5% to 69%. 

A. darlingi has appeared in very large numbers and on the 19tb of September, in one hour 
we captured no less man 460 specimens in the bouses; 140 were caught in a single room of a 
range situated in dose proximity of the cultivation. 

Hot a single A tartimacvlatut or A. albitarsis was found in the houses, in spite of the fact 
that the larvae of both these species were enormously abundant in all the surrounding irriga- 
tion eanala, outnumbering those of A. darlingi many times over. 

The causes of these unsual malarial outbreaks will le dealt with later under tie Leadicg 
Epidemiology. 




A. B C 


3 :-~The correlation of the distribution of malaria and that of A. darlingi ia not only 
geographical, but also topographical. This diagram refers to three separate villages 
belonging to the same East Coast estate, all situated within a radius of approxi- 
mately 1 mile. The vertical columns indicate the spleen rate, and the curve the 
„ number of Anopheles captured by searching the houses for 2 hours in each locality* 






MALARIA Iff BRITISH GUIANA, 143 

One o£ the estates, on the East Coast of Demerara, has its population distri- 
buted in 3 yards. In these the incidence of malaria varies within wide limits. 
On the 11th and 12th of August of this year, we carried out mosquito captures 
in the houses of these different yards, roughly the same time being devoted to 
each one. 

In the following Table we correlate the number of A . ddrlinyi captured to 
the spleen rate amongst the children in each yard : 


Table I. 


Yard : 

Spleen 

Rate : 

A. darlingi 
Captured : 

Yard A 

73.2 

430 

Yard B 

49.4 

172 

Yard C 

6.5 

1 11 


II. Domesticity of the Local Anophelines. 


The term 44 domestic ” does not apply sensn strirto , to any of the local 
species of Anopheles, as none of these is in the habit of breeding in water 
collections or containers, pertaining to houses or their immediate surroundings 
(rain water tanks, vats and barrels, sagging gutters, discarded tins, etc.) In 
systematic inspections carried out during the last 15 years, we have never 
found anopheline larvae in such waters. 

By “ domesticity ” we here mean to signify simply the tendency of these 
mosquitoes to enter houses. This is a point of very great practical importance, 
as it is an established fact that malaria is rarely contracted in the open. 

In the following Table we give the relative incidence of A . darlingi, 
A. tarsunaculatu8 and A. albitarsis in a series of 15,035 Anopheles captured in 
houses on the Guiana Coast during the last 4 years. 

Table II. 



Anopheles 

Captured. 

Relativ 

a Incidence 

Per 100 

Locality. 

A. darlingi . 

A . tarsimu- 
mlatus . 

A. albitarsis 

Tuschen 

503 

99.8 

0.2 

0.- 

De Einderen 

638 

99.4 

0.5 

0.1 

Uitvlugt 

452 

99.4 

0.6 

0- 

Wales 

815 

100.- 

0 .- 

0- 

Ogle 

120 

99.2 

0.- 

0.8 

Vryheid’s Lust 

366 

98.6 

0.3 

1.1 

La Bonne Intention 

788 

99.8 

• 0.- 

0.2 

Blairmont 

8,718 

84.- 

3.4 

12.6 

Providence 

1,289 

97.9 

1.9 

0.2 

Skeldon 

1.346 

100.- 

0.- 

0- 

ToTE 

15,035 

99.1 

0.2 

0.7 



144 AGRICULTURAL JOURNAL 07 BRITISH QUIAKA. f DC, 8* 

It will 1m noted that the domestioity of A. tarsimaculatns is consistently 
negligible throughout the coast ; only at Blairmoat A. albitarm wag o&ptured 
with a certain frequency; this is doe to the fact that the greater part of our captures, 
on this estate, were conducted in the village of Rampoor, which is situated 4 
miles inland, on the edge of the Abary cattle savannahs where this mosquito is 
often extremely abundant. In this locality we found that whereas A. darlingi 
was constantly present in the houses, in more or less consistent numbers, accord- 
ing to season, A. albitarm would be found fitfully, sometimes being absent, 
nsaally representing only 3 to 5 per oent., but occasionally as much as 15 to 25 
per cent, of the Anophelines captured. In the open, in this locality A. albitarm 
was always and by far the most abundant species from May to November. 


In this same locality we also noted that the great majority of A. albitarm 
captured in houses showed no evidenoe of having recently fed. This is well 
shown in the accompanying photographs. 


Table 1 demonstrates that A. darlingi is very definitely attracted to houses ; 
this is evidently, not the case for either A. tarsimaculatus or A. atbitarsis, The 
two latter species not rarely may be caught in estate hospitals or staff houses, 
where they are attraoted, like myriads of other night flyers, by the bright 
electric lighting. 


It might be argned that this different incidence in houses may simply be 
an expression of the different general incidence of the three species in the locali- 
ties we have studied. This is certainly not the case, as A. albitarsis and 
A. tarsimaculatns could always be found in numbers, when searched for in 
their habitual haunts ; moreover, the collection of larvae in surface waters (which 
was always carried out systematically and in parallel with the capture of adults) 
showed the larvae of these species to be constantly equally numerous, and often 
■very much more so than those of A. darlingi. 


III. Biting Habits. 

.4. darlingi is strictly a night flyer, becoming active soon after dusk. It 
undoubtedly bites man selectively. 


We have investigated the incidence of the various Anopheles in 
shelters such as stables, cow and sheep pens. In many instances we have 
carried out captures on horses tethered in the open in close proximity to houses 
in which A darlingi was present in large numbers at the time. 




Fig. 4 : — Ilmdom sample of -1. * hthnf/t ciptured in houses in the \ ill u;e of R unpoor (Blairmont) which is situated m 
land on the cdiye of the Aharv Sivamuh. With very few exceptions all aie gomed with blood. 

A t Jarlinji enters hou^c^ in large numbers and feeds on man select i\ elv . 




Plate ii, 



Fig. 5 : — Random sample of A alfutams ouirht in houses in the same village. AYith \er> few exceptions none appear 
to have fed recently, A albttcu ws enteis houses ictidentdlj and feeds seiectiv elj on animals, cattle, horses 
and sheep in particular, both in shelters and in the open. 



MALARIA IN B&mgB GUIANA. 


145 


The following Table summarizes oar findings : 

Table II. 


Locality. 

Anopheles 

Captured 

Relative Incidence Per 100 

A. darlingi 

A. tarsima- 
culatus. 

A . albitast8 

] . . 

De Kinderen 

67 

11.9 

85.1 

: ’ 

3- 

Uitvlugt 

67 

0- 

98.5 

1.5 

Wales 

14 

7- 

93- 

0- 

Blairmont ") 

Bath } 

1,883 

2.3 

52.5 

45.2 

Providence ) 

Skeldon ! 

| 135 

5.2 

3- 

91.8 

Industry 

(Corentyne Coast) 

533 

l 

0- 

1 

99.1 

! 

! 0.9 

Total. 

2,61)'* 

2.2 

i 

, 39.9 

37.9 


A. tarsimaculatua and, more especially, .1 albitarsis when disturbed from 
their resting places in close proximity to their breeding sites, will frequently 
attack by day even in full sunlight. 

On the back dam of the Western Berbice estates and on the Abary 
savannahs *4. albitarsis may be very troublesome even by day. 

All our observations, in conclusion, tend to show that .4. darlingi is 
definitely anthropophilous in its feeding habits, i.e„ it feeds on man selectively and, 
to this purpose, it enters and rests in houses in large numbers and, presumably, 
if conditions are favourable, it may fly considerable distances in search of its 
favourite meal. 

A. tarsimaculatua and .4. albitarsis are, on the contrary, strictly ioo/diilous, 

they feed selectively on animals ; for this reason their favourite haunts are 
animal shelters of various description. 

IV. Conclusions. 

Reviewing the data which have been presented in this and the previous 
section, we are led to the following conclusions : 

4 

(1) There are three species of Anopheles, in this Colony, which by their 
number and wide distribution must be regarded as possible vectors of malaria. 
These species are A. tarsimaculatua, A. albitarsis, and .4. darlingi. The 
existenoe of the latter two species in this Colony was not previously known, 
both having been confused under the erroneous denomination of .4. argyri * 
tarsia, a species which, though valid, we have failed to find in British Guiana. 



146 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[IX, 3. 


(2) An investigation on the local geographical and topographical 
distribution of these three species of Anopheles reveals that the distribution and 
incidence of malaria is strictly parallel to the distribution and incidence of A. 
darlingi, a species which enters houses and feeds on man selectively. A. 
tarsi maculatw and A. alhitarsis abound in localities which are habitually free 
from endemic malaria ; when malarial epidemics occur we have always been 
able to demonstrate the presence of A. darlingi ; the severity of such epidemics 
is directly proportionate to the incidence of this mosquito. 

(3) A. tarsi maculatw and A. alhitarsis, which abound on the pastures, 
sugar and rice plantations and on the savannahs of the Coast and far interior, 
bite animals selectively and cattle in particular. They enter stables and cow- 
sheds in search of food; human habitations only accidentally. A. alhitarsis 
even when caught in houses rarely shows evidence of having fed on the 
occupants. The absence of endemic malaria in localities where only thoBe two 
species abound, as at Bath and on the Corentyne Coast, is easily explained; 
these species, by feeding selectively on animals, are not liable to acquire and 
thereby, subsequently, transmit malarial infection. 

(4) We have ourselves been able, without difficulty, to infect in the 
laboratory locally bred A . tarsi maculatw and A. alhitarsis with local strains of 
malaria parasites, ( P . vivax ), but we are of opinion that the importance of both 
these species is negligible from a malariological standpoint : in order to be an 
effective carrier a mosquito must bite not once but repeatedly : it must feed, in 
the first place, on a human subject harbouring malaria parasites in a suitable 
phase; after an incubation period of at least 10 days the mosquito becomes 
infective, but, evidently, in order to transmit malaria again to one or more 
persons it must again feed on man, on one or more occasions. The figures and 
observations we have recorded which, we believe, are based on adequate material, 
were collected over an adequate field and for an adequate period, evidently 
show that both for A , tarsimaculatus and A. alhitarsis , the likelihood of such 
repeated attacks on man by an individual mosquito is sufficiently remote or, at 
least, unusual to lose all practical importance. 

(5). We, therefore, ultimately conclude that A, darlingi is the sole 
malarial vector of practical importance in this Colony. 


(To he Continued). 



COCONUT WILT IN ESSKQUIBO AND POMEKOON 

DISTRICTS. 

BY 

D. W. DPTIIIE, ph. D., F.I.C. 

( '/trill in/. 


I. General. 

Wilt disease of coconuts has existed for many years in the Caribbean area, 
and it has been the subject of several investigations. Follett-Smith (Ann. Rep. 
Choni. Div. 11)30 p. 107) made one of the earlier investigations of the disease, 
but he found the evidence so conflicting that he made no definite statement, 
apart from noting that there was a higher content of available phosphate in the 
soil of healthy ureas as compared with affected areas. Recently, Bain published 
the results of a long investigation of Trinidad Wilt (Bull. Dept, of Agric. 
Trinidad, 1037) and explained the disease as being duo to the curtailment of 
root growth by a high water table at certain times of the year, followed by dry 
soiisons which the restricted root system could not withstand. This explained 
the puzzling fact that trees grow normally for several years, as even a 
relatively small root system is sufficient to keep young trees in good health, 
but the strain of bearing is usually the critical [mint. 

II. Coconut Wilt on the Kssbouibo Coast. 

b'irhl ObmTatiam. 

Trees 15-25 years old are affected, and the symptoms are almost 
identical with those in Trinidad — the lower leaves show a characteristic 
bronzing at the tips, the nuts are shed, the remaining leaves wither, and finally 
the whole crown falls. A noteworthy feature is that, generally speaking, the 
disease moves in the direction of the prevailing wind. 

The disease occurs both on clay and on sand, but the sandy areas are so 
small in proportion that they were omitted from the present investigation, as 
only limited time was available for field work. 

Soil Sump! i ni/. 

Top soil andBubsoil samples (0-12 inches and 12-21 inches) were taken in 
three areas on Pin. Laud of Plenty, vizi — 

(a) A healthy bed in a heavy clay area (Field No.- 1 Chinee Land) 

(b) An adjacent bed in the same field, in which the trees were all affected. 

(c) A field some distance away (Three Friends South, Cross Dam Field) 
of similar flail typo, in which the trees had completely wilted about two years 



14 $ AGRICULTURAL JOURNAL OP ShifISR GtJlANA. flX, 3 . 

before, since when the land had been covered with bush. It had recently been 
cleared for planting ground provisions. 

Soil Analyses. 

The complete analytical data are given in Table I. 

Table I. 

Analyses op Soil Samples from Pln. Land op Plenty, Esbequiro Coast. 




Field No, 1 Chinee 
Land Healthy Bed 

Field No. 1 Chinee 
Land Vfili Area 

1 3 Friends Cross Dam 
'Field Wilted, then in 

1 bush 2 years. 



E 430 

E 431 

E 428 

E 429 

> E 432 

E 433 

Depth 


0—1 ft 

1—2 ft. 

0—1 ft. 

1-2 ft. 

^ 0-1 ft. 

1 

1-2 ft. 

Normal Reaction (pH) | 

Exchange Reaction (pH) i 

49 

5.0 

4.7 

4.9 

4.9 

4,8 

3,9 

4.2 

3.8 

4.3 

3.7 

3.7 

% sand 


3.3 

23 

3.8 


0.4 

6,7 

Index of Texture 


37 

40 

38 

38 r 

35 

1 .13 

% Soluble Salts 
y o Organic Matter % 


0.009 

0.283 

0,158 

0.433 

0.012 

1 0 050 


153 

1.30 

2.98 

2,40 

1.97 

1 43 

°L Nitrogen 


0.158 

0.105 

0.172 

0 112 

0.147 

' 0.119 

Carbon/Nitrogen ratio 

5.0 

7.2 

10.1 

12 9 

1 8.0 

1 0,9 

Lime Rqt. Tons/acre 6" 

00 

3 7 

80 

44 

8.3 

i 7.4 

Avail P, 0, p.p.m. Tiuog 

ml 

1 ml 

ml 

ml 

nil 

> nil 

Exchange , 

(CaO ! 

333 

i 2.35 

3.05 

3 44 

2.18 

! 2 02 

& Water Sol, j 

1 MgO 

5,30 

I 1105 

8.05 

12 05 

4.51 

! 7 72 

Bases j 

|K,o 

0.14 1 

i 0 25 

0 21 

0.18 

0.29 

0.09 

Mg cqvs/100 gms 

lNa,0 j 

: 1,80 

! 5.38 j 

! 

2.38 | 

4.02 

0.37 

0.5O 


This soil may be described as an acid clay, markedly deficient in available 
potash and phosphate, but with adequate nitrogen and organic matter. It should 
be noted, however, that coconuts normally grow on poor soils, so it cannot be 
argued that potash and phosphate are the limiting factors. The significant 
figures are those for per cent, soluble salts and per cent, exchangeable magnesia 
and soda. They indicate that the Chinee Land field soil is suffering from lack 
of aeration and drainage, since there is an accumulation of saline substances in 
the subsoil. But this is not due to waterlogging, as the soil was quite dry at the 
time of sampling, even though there was standing water in the drains between 
the beds. Some attention was therefore focussed on the water relationships 
of this soil. 

Soil Moisture. 

The rainfall from 1st January to the date of sampling (24th March) was 
abnormally high : 11.6 inches fell in January, 6.25 inches in February and 

13.11 Inches from 1st to 24th March. Most of the drains contained water, but 
the soil in the centre of the beds was by no means sodden. An attempt was 
made to find the water table, but this oould not be reached with a 2*— ft. auger 




COCONUT WILT Itf ESSBQUlBO AND POllKROOJf DisTRIOTP. 149 

even by boring less than six inches away from a drain containing water. Thus 
the peroolation of both rain and drainage water is extremely small, and soil 
samples from the healthy bed in Chinee Land Field were taken in sealed tins 
(0-6", 6-12", 12-18" 18-24") for moisture determinations. Table II gives the 
detailed results, along with approximate figures for the Wilting Point of the 
soil, i.e., that moisture content at which the plant is unable to overcome the 
attraction of the soil for water. These figures show that the soil had a gross 
moisture content of about 25 per cent., the danger point being about 13 per cent. 

Table II. 


Soil Moisture Relations of Healthy Coconut Bed at 

Land of Plenty. 


Depth 

' 0-6" 

6-12" 

12—18" | 

18—24' 

Gross moisture % 

1 23.0 

24.0 

| 26.0 ; 

27.6 

“ Sticky Point” moisture % (P) 

32.8 

37.8 

. 35.2 1 

32.7 

Sand % 

3.3 

3.3 

2.3 ! 

2.3 

Wilting Point moisture % 
[0.37 (P - 1/5 sand)] 

! 

12.0 

13.8 

13.0 t 

12.0 


i 


Thus in spite of the heavy rainfall of the previous three weeks, the soil had 
only 12 per cent, available moisture, and in dry spells it would probably 
approach the danger point, which may be even higher than 13 per cent, on 
account of the comparatively high salt content of the soil (i.e., magnesia and 
soda). 

Hoot Distribution. 

Further observations confirmed the suggestion that movement of water in 
the compact clay might be the key factor in the disease. Trenches were dug 
round two trees, one which had died about two years before, and one which 
was Just beginning to wilt, and their root systems were examined. Approxi* 
mately 50 per cent, of the roots were found in the top 6 inches, about 25 per 
cent, in the second 6 inches, and the remainder were sparsely distributed down to 
four feet. The roots tapered off rapidly from the base of the tree, and it was 
evident that they were not finding it easy to penetrate the stiff clay. A distinct 
colour change in the soil was noted at 15 — 18 inches from the surface, being the 
depth to which cultivation had been reached when the land was tinder 
eugar-cano. , 

Cause of the disease . 

The roots of forest trees and bush penetrate into the soil as far as six feet 
even in a heavy clay, and thus aeration and drainage are maintained Jar below 
the surface. If the trees are cut down and another tree crop, such as coconuts* 
is planted, tie young trees will have an opportunity of sending their roots 



i56 


AGRICULTURAL JOUftttAt Of BRITISH GUlAtJA, ' 


[IX, 3. 


equally far into the soil. Changing from bush to coconuts does not cause any 
great change in the soil structure, and even on poor soils where this change 
has taken place, the coconuts have given good yields over many years. 

The widespread cultivation of sugar-cane in this Colony led to large areas 
being changed from bush to sugar-cane — a shallow-rooted grass crop which 
exploits the top 18 inches of the soil and leaves the lower layer's free from roots . 
The soil ecology was drastically altered, since the topsoil was intensively 
cultivated and the lower layers were allowed to become compact and “ lifeless,” 
On heavy clay lands the natural drainage was thus impeded and an elaborate 
drainage system had to be constructed in order to get rid of excess water as 
rapidly as possible. 

When economic conditions led to the abandoment of many sugar estates, 
coconuts were planted on some of the old cane beds, and the young trees found 
themselves in a well-drained highly organic topsoil, which favoured their 
rapid growth. As the roots passed down from the cultivated layer, they 
found a saline, compact clay with little oxygen f and a limited water 
supply, and thus the greatest root development took place in the 
surface soil. A jnass of roots developed near the surface which further hindered 
the penetration of water, and the added strain of bearing fruit left the trees 
undernourished and sickly. 

The coconut tree is sufficiently hardy to withstand lack of soil nutrients, 
but a good water supply is essential, and in dry periods the soil on the windward 
side of a field would rapidly dry out and approach the “ wilting point”. If a 
few trees died, their shade would be removed, lack ot* moisture would affect the 
neighbouring trees, and wilt would gradually move in the direction of the pre- 
vailing wind. 

It is significant that fields which appear to be waterlogged, overgrown with 
bush, and generally ‘ 4 neglected’*, do not show signs of wilt, and the natural 
reaction of the planter is to consider these good fields and to underlmsh and 
improve the drainage whenever the price of copra rises. By doing this he is 
aiding the rapid run-off of water, increasing the evaporation from the surface 
of the soil and possibly causing wilt to appear, 


To sum up, wilt disease of coconuts on the heavy clay soils of the Essequibo 
Coast is probably caused by planting coconuts on old cane beds, where the sub- 
soil is too compact and saline to allow easy root penetration, with the result 
that the topsoil becomes a mass of roots, and percolation of water is greatly 
hindered. The trees are thus, living on the verge of drought, and ** physiologi- 
cal drought” will also play an important part, owing to the high content of 
magnetfa and soda even in the topsoil. When evaporation from the soil surface 
is increased by “ clean-cultivation” or by the death of a few trees, wilt appears 
and spreads slowly in the direction of the prevailing wind. 



COCONUT WILT IN EB8EQUIBO AND BOliEROON DISTRICTS. 


151 


Cure and Prevention . 

It is clear that soil aeration and water penetration mnst be improved, but 
the thick roots of the coconut tree render inter-cultivation very difficult. It 
might be feasible to use a harrow, gradually going deeper and forcing the roots 
down, but this would not improve the subsoil, and it would be difficult to im- 
prove the condition of trees which are threatened with wilt. Planting 
windbreaks, encouragement of deep-rooted woody ground cover, and even 
flooding for short periods might ameliorate the condition to some extent, but the 
subsoil conditions would probably remain the same. Mr. S. H. Seymour of 
Pin. Affiance has suggested the use of dynamite to shatter the subsoil when it is 
dry, and this is wortli trying, as it may even be economic on a fairly large scale. 
Oil geologists have recently used dynamite in conjunction with seismographs, 
in order to interpret the deep strata, and thus the effect might be more wide- 
spread than is generally supposed. 

With regard lo fields which arc to be replanted with coconuts the procedure 
is straightforward. Flood-fallowing for long periods — over twelve months— 
would probald y do much to improve the subsoil conditions, but the safest method 
would be to leave the land in bush for a few years before replanting. Table I 
gives the soil data for a field (Three Friends South, Cross Dam Field) in which 
the coconut trees had all wilted and the area had been left in bush for about 2 
years. There is a marked difference in the subsoil from that of the Chinee 
Land Field, as the saline components had been partly removed. In this field the 
surface soil was much more friable than in the Chinee Land Field, and it is 
probable that a longer period in bush would improve it even more. 

These arguments and considerations were the result of discussions in the 
field with the Deputy Director of Agriculture, the Agricultural {Superintendent, 
Essoquibo, Mr. S. II. Seymour (Pin. Affiance) and Mr. E. Taylor (Pin. Laud 
of Plenty) and thanks are due to them for valuable information and suggestions. 
The soil analyses were carried out by the Assistant Chemist, Mr. C. L. C. 
Bourne. 


III. Coconut Wilt on the Pomeroon River. 

Several small areas on the banks of the Pomeroon River have been planted 
In coconuts, on soil which varies from deep pegasse to pegassy clay. The trees 
grow particularly well at first, come into bearing very early, sometimes when only 
three years old, but they wilt at about 10 years. An area which lias been 
replanted after wilting will show equally good promise, but it may show signs of 
wilt after 7 or 8 years, and repeated planting appears to shorten the life of the 
trees to as little as 5 years. Generally speaking trees on the dams grow well, 
even on clay, and they may live for 20 to 30 years without showing signs of wilt. 

Field observations showed that the conditions fitted Bain’s explanation of 
Wilt in Trinidad. In wet seasons the water table at high tide is 18 to 24 inches 
below the Surface, the soil is well aerated and conditions are admirable for the 



152 AGRICULTURAL JOtffttfAL OP BRITISH GttlAifA. [IX, 1 

growth of trees while they are young. Root growth is limited by the high 
water table, and thus the trees die when their root systems develop beyond a 
point which depends on their height above the river. Cultivation and aeration 
of pegasse causes it to shrink rapidly, and thus the water table is nearer the sur- 
face when the field is replanted after wilting. 

Dwarf Coconuts might survive longer under these conditions, but the most 
satisfactory remedy would be to plant coconuts only on land which is at least 
6 feot above the water-level of the river at high tide, as proved by test borings. 



A GRADE DAIRY HERD. 

BY 

H. A. FRASER, B.V.Sc., 

Government Veterinary Surgeon ( Ag,). 

One of the principal objects for the establishment of this herd was to 
demonstrate that a good grade dairy herd could be made an economic success 
in British Ouiana and also to provide reliable data on the various problems 
arising. 

Intensive methods of production have been employed, as land carrying a 
dairy herd bears a high rental owing to the fact that it needs to be reasonably 
well drained and to have a reliable water supply throughout the dry season 
for the pasture. 

The herd was started in 1929 with two cows, and by 1932 nine head were 
added. In 1933 it was put on a commercial basis, and from then to 1934, 11 
head were purchased. Since then, no further additions to the herd by purchase 
have been made, as improvement was very disappointing and uniformity difficult 
to attain through animals whose ancestry was not known. In dairy herd improve- 
ment the only sound and economic breeding policy is to breed the best to the 
best, therefore only purebred bulls were used on the best cows, all low 
producing animals were weeded out, and the female calves raised for replace- 
ment. Thus improved production and uniformity were gradually attained. 


The following Table shows the number and classification of the herd at 
half year ending June 30, 1938: — 

Table I. 



Cows 

| Heifers 

1 Bulls 

Total 

Parebred Guernseys 

3 

i 

— 

4 

„ Holsteins 

3 

4 

— 

7 

1st grade Holsteins 

7 

6 

— 

13 

2nd „ „ 

7 

8 

— 

15 

3rd M «» 

2 

2 

2 

6 

4-tli h «« 

— 

2 

1 

3 


22 

23 

3 48 


It will be seen from the foregoing table that all the Creole milch cows that 
had been originally purchased were disposed of, and the present herd are all of 
improved breeding. 

The first cross heifers in milk that were not up to standard were sold at a 
good price, and there has been a steady demand by buyers for grade milch cows 
or heifers in calf. Unfortunately, the same cannot be said of grade bull calves, 
— cattle-owners seem disinclined to buy good grade bulls to improve their herd, 
although there has been an improvement in the sales of these this year. 

Table No. II, is given from a productive point of view and shows the 
number of days cows have been milked and the quantity of milk obtained 
during each 'lactation. 



154 


AGRICULTURAL JOURNAL OP BRITISH GUIANA, 


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[IX, 3. 



A GRADE DAIRY HERD. 


155 


The highest daily yield of 41 pints milk was obtained this year from 
“Elsie,” a purebred Holstein cow born in the Colony. In 31 days she 
produced 1,502 lb. milk and seems likely to complete her lactation with 12,000 
lb. for the year. “ Bessy 2nd,” a second cross Holstein cow freshened with 36 
pints milk per day and a total yield of 8,834 lb. milk in 357 days. “ Maokie,’’ 
another seoond cross Holstein cow, gave 34 pints milk per day and a total of 
10,063 lb. in 415 days. There are also other grade cows that have given 36 
pints daily, but have not yet completed their lactation. These yields are 
especially gratifying as the animals are under the nsnal routine of feeding and 
management. 


MILK PRODUCTION. 

The production of milk has continued to increase. 
Table III shows the annual production. 


Table III. 


1033 

1034 

1035 
103(5 

1037 

1038 (8 months) 


12,028 pints 
28,862 „ 
35,083 „ 
50,980 
50,005 „ 
50,000 „ 


The work of grading up the herd with purebred Holstein bulls has been 
carried on ; the young animals of the fourth cross are showing the characteristics 
of the purebred Holstein. 

Tabic IV shows the pedigree of Bessy 4th, a fourth cross Holstein heifer 

Table IV. 

Sire 

(Demerara Kerk 


JJosxj 4 tli 


[Dam 


Sire __ 

Sir Rochani 
Kerk 


[ Sire 
i Pontiac 
I Jew el de Kol. 


Bossy 3rd. 


Dam 

Bessy 2nd 


Dam 
Bess) 1st 


Sire 

Texas Wonder 
Dam 

Creole Cow. 


There are only two crosses more to attain the top grade which is considered 
purebred, btft is not eligiblo for registration in the herd book of the breed. 



ISfl * AGRICULTURAL JOURS AX OP BBITISS GUIANA, [IX, 3, 

Table V dearly shows how the grade blood disappears!— 


Table V. 


Generations. 

Sire’s % 
of purity. 

Dam’s % 
of purity. 

Offspring's % 
of purity. 

Percentage of 
unimproved blood. 

1st cross 


0 

50 

50 

2nd „ 



75 

25 

3rd „ 


75 

87.5 

12.5 

4th „ 


87.5 

93.75 

6.25 

5th „ 


93.75 

96.87 

3.12 

6th „ 


96.87 

98.44 

1.56 


Grading up is the cheapest and most economical method of herd improve* 
ment. The following table showing production and net income of Holstein 
grades and Creoles nnder similar conditions serves to indicate the important 
part that a purebred sire plays in improving the herd. 


Table VI. 


Breed 

Lactation 

Period 

Total 

Yield 

Milk fed 
to calf 

Milk sold 



Net 

Income 




lb. 

lb. 

lb. 


Creole 


4th 

3,302 

1,558 

1,774 

19.88 



5th 

2,738 

1,556 

1,172 

5.19 

» 


6th 

3,543 

1,734 

1,809 

25.80 

** 


4th 

2,738 

1,650 

1.088 

i 4.49 

»» 


5th 

2,330 

1,526 

864 

— 5.52 Loss 

** 


6th 

2,807 

1,614 

1,193 

i 3.44 

Holstein 


4th 

6,014 

1,806 

4,208 

108.98 

1st Cross , 

\ 

5th 

6,222 

1,798 

1,424 

108.32 

,, J 

1 

6th 

6,470 

1,780 

4,690 

122 83 

Holstein 1 

L 

1st 

5,260 

1,770 

3,490 

J 81.47 

2nd Cross 1 

r 

2nd 

9,712 

1,770 

6,142 

1 164.35 


The above shows that the Creole cow even when carefully selected has no 
place in economical dairying. The lactation period is too short, only abont 
eight months, while the Holstein grade will milk for a year or more. The 
oomgarison was made over a period of 3 years and all the animals came into 
lactation within a few weeks of each other, so that seasonal conditions were 
practically the same for each trial, AU the Creole animals were disposed of 
after this experiment, 







Plate iii. 



Fig. I : — ‘‘Orchard Leigh Heilborn Mercedes/ 1 A pureberd Holstein-Fricsian Bull 
owned by the Department of Agriculture. 



Fig, 2:—' “Candies Carbine. 11 A purebred Guernsey Bull owned by the Department 
of Agriculture. 


Plate iv. 



Fig. 3 A Grade Holstein-Creolc. Herd. 



Fig. 4:— Grade Holstein- Creole Calves, 10—12 months old, reared on a commercial qalf meal feed. 




A GUAM DAIRY HERD. 


157 


Calves are allowed to suckle their dam 24-36 hoars after birth to obtain 
the colostrum. They are then removed from their dam and fed milk from a 
pail until weaned at 6 months of age. For the first two weeks of life, the yonng 
calf is fed 6 pints of milk daily divided into three feeds. Thereafter the milk is 
increased to $ pints daily, and is given in two feedings. After the third week, 
concentrates and grass are fed in addition to milk, the concentrates being in- 
creased gradually every month so that by the 5th month the calf is getting 4—5 
lb. daily and all the grass it will eat. Glean drinking water is available at all 
times ; this is an important detail that should not be neglected ; calves fed under 
this method are thrifty and well grown when weaned. The cost of feeding 
whole milk from birth to weaning is however, rather high, averaging about #70 
as the following table shows : — 


Table VII. 


Months. 

Weights. 

Total Feeds. 

Daily 

Gam. 

Cost per month. 

1st month 

lb. 

65 

birth 

weight 

110 

lb. 

Milk 270 
Grain 12 

lb. 

147 

10A6 

! 

1 

2nd month 

165 

Milk 252 
Grain 15 

1.89 

1 

i 9.88 

3rd month 

210 

Milk 304 
Gram 78 

145 

12.56 

1th month 

240 

Milk 300 
Grain 90 

100 

13.05 

5th month 

310 

Milk 310 
Grain 121 

.• 2.26 

14.00 

6th month 

310 

Milk 192 
Giain 159 

1.00 

*10 00 





#69.95 


Calves were reared somewhat cheaper this year than formerly, by feeding » 
limited amount of whole milk and then substituting gradually an imported calf 
meal. Unfortunately the calf meal was finished during the 5th month so that 
the experiment could not be carried out for the full period, as the meal could 
not be obtained locally. The growth and condition of the calves were quite 
good and the ayerage cost was 138 per calf. This large saving in the cost of 
rearing calves should be of great help to local dairymep, 



158 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[IX, 3. 


After oalves were weaned they were pnt'on to good pasture, and all grain 
feeding discontinued. It was noticed that up to about the sixteenth month of 
age growth had practically oeased but condition was maintained. After the 
sixteenth month, however, the rate of growth increased rapidly and good gains 
were made. Calves fed grain up to about the 14th to 16th month were pat on 
good pasture ; no appreciable setback occurred in the rate of growth and gains 
were good. 

Why growth should almost cease from weaning to the sixteenth month 
seems to be explained by the fact that the digestive system of the weanling is 
not able to assimilate the nutrients in grass necessary for growth as the digestive 
system of the older animal is abie to do. 

In order to obtain accnrato information as to normal growth, monthly 
weights and measurements for height were made on 12 calves as Table VIII 
shows. 


Table VIII. 


% 

Age in Months 

Height at Withers, | 

Inches. , 

Weight 

lb. 

Birth 

28 1 

73 

1 

29.5 i 

110 

2 

31.5 ! 

142 

3 1 

32.7 

184 

4 

34 

210 

5 

36 

260 

6 

37 

296 

7 

38.2 

320 

8 

39.5 

356 

9 

40.5 

394 

10 

41.5 

421 

11 

42 

442 

12 

! 

43 

473 


It is intended to keep on with this experiment until the animals are 24 
months old, should weighing facilities be available. 

The following is the weight of two animals that were put on pasture at 8 
months of age and have since received no grain. 

Height Weight 

f4th month 41.5 389 

15th month 42.2 396 

Many -of the dairymen of this colony do not feed their calves adequately. 
The allowance of milk is too small for growth and after the weaning period very 
little grain is fed. Therefore many of these animals are not big enough to bp 



A GRADE DAIRT HERD, 


159 


brad until they are over 3 years, and do not come into production until they are 
4 years and over. 

Hjeifers that are veil grown are bred at 18 to 20 months old. In order to 
maintain growth and development it is neoessary to feed concentrates during the 
gestation period. 

. Feeding Stuffs. 

The feeding of grain is one of the most expensive items of expenditure. The 
continned rise in the price of local foodstuffs and the uncertainty of obtaining 
regular supplies were two of the most disturbing factors throughout the year, 
thereby increasing the cost of production. The margin between the cost of 
production and the selling price of milk is so small that when foodstuff prices 
increase above the small seasonal fluctuation, it tends to disappear very quickly 
and a loss occurs. 

The value of a feed is largely determined by its composition and palatability. 
If deficient rations are fed the milk supply will drop, consequently some 
dairymen do not get as good yields of milk because of poor feeding. 

Rice bran, broken rice and coconut meal are the principal concentrates used, 
but require a high protein feed such as linseed meal, soya bean meal or cotton- 
seed meal to balance the ration. 

Molasses is a good feed as it helps to make the food more palatable and 
reduces the cost of the ration. 


The following ration has been used with good results. 


Rice bran 

100 lb. 

Coconut meal 

50 „ 

Soya bean meal 

20 „ 

Linseed meal . 

10 „ 

Molasses 

20 „ 

Bone meal 

4 „ 

Salt 

2 ,. 

•* 

e above ration fed 

to a cow in milk is 


gallon of milk produced. 

Bone meal has always been included in the ration as the grasses are 
somewhat low in mineral oontent, chiefly lime and phosphorous. 


Pasture. (26 acres). 

i 

This has been the second year of pasture improvement and it serves to 
demonstrate the value of rotational grazing on improved grasslands. 


When the pasture was first leased it was of a very poor type consisting 
chiefly of a tough wiry sedge, black sage and a few varieties of grass. It had to 
be completely fenced and was subdivided into paddocks. The sedge and sage 
weye cut and burnt and part of the area was ploughed and planted wit|i far^- 



160 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 3. 


grass, Indigofera and Demerara Primrose. Only one paddock was manured with 
140 cartloads of barnyard manure as the rainy season commenced and stopped the 
work. When the pasture was ready for grazing the cattle were turned on and 
allowed to graze the paddooks in rotation as Table IX shows. 


Table IX. 


Paddocks 

Head cattle. 

Grazing days continuously 

No. 1 

9 

From Feb. 19 to Apr. 18 — 60 days 


12 

„ June 7 to Aug. C — 60 „ 

No. 2 

14 

From Aug. 24 to Sep. 13 — 21 days 


12 

„ Dec. 1 to Dec. 24 — 24 ,, 

No. 3 

9 

From Apr. 19 to June 10 — 21 days 


10 

„ Sep. 14 to Oct. 31—48 „ 

No. 4 

15 

From Aug. 7 to Aug. 19—13 days 


10 

„ Nov. 1 to Nov. 13 — 13 „ 

f 


The animals were in good condition and did well on pasture but were not 
grain fed as they were dry cows and young heifers. 


Water was taken in during the dry weather to irrigate the graSB and keep it 
growing ; so that 2,040 lb. grass was cut and cured as hay and fed when grass 
was scarce. 

The response of the pasture to management is manifested in the marked 
increase in the variety of grasses and in indigenous legumeB thug increasing its 
nutritive value and its carrying capacity. 

To improve pasture one must be asiured of reasonable drainage and a 
water supply for the dry months. These two essential requisites indicate that 
such land must bear a fairly high rental and thus only improved stock of high 
production could pay for its improvement. If dairying is to expand and 
become an industry these facts must bo considered and the general principles 
ot live stook management be applied. 

Diseases. 

The general health of the herd has been quite good. 

Tuberculosis. 

The intradermal Tuberculin test was done for the detection of tuberculosis, 
but no animals reacted to the test thus indicating that the herd is free from 
infection. Yearly tests will be made in future as a routine measure. 

Mastitis 

There was one very acute case that resulted in the loss of one of the 
quarters of the udder. There were three other mild cases occurring soon after 




A Grade dairy herd. 


161 


parturition, of cows with large bags bat these yielded readily to treatment. The 
faot, however, should not be forgotten that the higher the herd is graded op to 
heavier producing cows the greater will be the tendency to the occurrence of 
Mastitis. Cows most be milked with clean and dry hands, the udder kept clean 
and the animal well bedded so as to control as much as possible the external 
factors that contribute to diseases of the udder. 

Breeding irregularities. 

There was a marked improvement in getting the cows back in calf due in 
a large measure to having a stud bull on the farm instead of having to take the 
oows to the Government Stock Farm to be bred. 

Sporadic abortion . 

In the latter months of 1935 five cases of abortion occurred within a period 
of 2 months, and with cows in varying stages of gestation, at the 7th, 5th, 4th 
and 3rd months. 

This increasing number of abortions occasioned a great deal of anxiety as 
it was feared that the bacilli of infectious abortion might have been introduced 
into the herd through a recent purchase of a purebred Holstein cow from a herd 
that had some breeding troubles. 

The Agglutination tabe test for infectious abortion was made. The litres 
used were a 1 : 25, 1 : 50 and 1 : 100 dilution. Known positive and negative 
sera were used as controls. 

After 48 hours incubation at 37.5 degrees Centigrade the tubes under test 
did not show any agglutination thus indicating that the animals were free from 
infectious abortion. The positive antigen control tube showed complete 
agglutination in 1 : 100 dilution. 

Strict hygienic measures were carried out'and all aborting cows isolated 
from the herd and treated. They were subsequently rebred and have calved 
regularly without any further trouble, and no further cases have ’occurred in 
the herd. 

Breeding troubles* if neglected, increase every year in a herd and cause a 
reduction in milk production and an increase in oost of production. 

There is* however* a fairly high percentage of sterility cases among the 
milking herds on the coastlands and some work would need to be done to 
determine the causative factors and its prevention. 

Table % shows the percentages of expenditure under their respective 
headings. 



162 1 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


£lX,l 


Tablb X. 


Year 

Wages 

Feed 

Pasture 

Sundry 

Expenses 

Buildings 

Total 


per cent. 

per cent. 

per cent. 

per cent. 

per cent. 

per cent. 

1934 

42.78 

41.18 

_ 

4.24 

11.80 

100 

1935 

40.41 

48.89 

— 

7.49 

3.21 

100 

1936 

39.90 

39.03 

8.93 

12.14 

— 

100 

1937 

34.83 

40.30 

7.86 

11.53 

5.48 

1 

100 


It will be seen that in 1937 the benefits derived from the pasture show a 
redaction of the feed and wages bills, the two items of heaviest expenditure. 

As the rainfall has an important bearing on dairying by keeping the grass 
growing over a longer or shorter period, daily records were kept for 1937. The 
rainfall for the year was 82.24 inches. The firBt 19 days of Janaary 10.26 
inches of rain fell and thereafter a short dry season occurred to April 18, with 
only 2.91 inches which caused a scarcity of grass. The mid-year rainy season 
commenced on April 19, to Angnst 23, with a rainfall of 52.14 inches. Daring 
the wet period grass was abundant. Daring the second dry period Aagast 24, 
to December 18, 8.07 inches of rain fell. This kept the grass growing until the 
middle of November when the weather became exceedingly hot and a scarcity of 
grass occurred. 


SUMMARY AND CONCLUSIONS. 

1. That it is possible to build up a profitable grade herd of dairy eattle by 
using purebred bulls on creole cows. 

2. In milk yield the grade cow compares most favourably with the pure* 
bred, is hardier and more economical with feed. 

3. The creole oow has no place in economical dairying. 

4. The cost of rearing calves can be considerably reduced by feeding a 
limited amount of whole milk and substituting a calf meal. 

5. The cost of local feed stuffs is high, and the supply not dependable. 

6. That with the improvement of breed, there must also be an improve* 
tnent of the food supply. 

7. That with a reasonable amount of drainage, the coastal pastures can be 
Improved by fencing, manuring and rotational grazing. The carrying capacity 
and nutritive value are increased and dairying can be considered an alternative 
to rice farming. 








A MILLING TEST ON SIXTY PADI VARIETIES. 

BY 

D. W. DUTHIE, ph.d., p.i.c., Chemist. 

AND 

C. L. 0. BOURNE, Assistant Chemist. 


I. Method op Testing. 

One difficulty in padi selection and breeding work is that a variety which is 
suitable from the point of view of cultivation i.e., yield, lack of “ shattering,” 
strength of straw, etc., may give a high breakage percentage on parboiling and 
milling. A method was therefore developed by which small quantities of the 
different varieties could be tested under standard conditions of parboiling and 
milling. 

Soaking and steaming were carried out by a laboratory adaptation of the 
method in general use in this Colony, and a high degree of efficiency was 
attained on account of the smallness of the samples (up to 300 grms.). The padi 
was placed in a conical flask, covered with water at 80"C (176°F), which 
immediately fell to 60°C when in contact with the padi. The flask, with a 
loose glass stopper, was left overnight (18 hours) in an electric oven, set at 
60°C, which maintained the steeping water at 50 — 55 "C (120 — 130°F.). A 
photograph of the steaming apparatus is given, showing how the steam is led 
from a copper boiler through a glass tube which nearly reaches the bottom of 
the inverted flask, the outlet for waste steam and condensation water leading 
downwards from the neck of the flask. The padi was steamed for 4 minutes, 
its temperature being about 100°C, as the steam was not under pressure. The 
steamed padi was dried in the sun, but considerable difficulty was experienced 
in standardising the temperature of drying. By a series of tests it was found 
that breakage due to rapid' drying coqjld be avoided by sun-drying under a 
muslin shade, thereby keeping the temperature of the padi below 38°C (100°F). 
Drying was continued until the padi had a moisture content of 12 or 13 per 
cent. 


Milling was carried out in a small-scale machine manufactured by Messrs. 
Guidetti and Artioli, Vercelli, Italy, in which small samples of padi (e.g., 100 grms.) 
fan be hulled and polished in a manner which approximates to that in a large- 
scale mill. The machine consists of a carborundum disc huller, a carborundum 
cone polisher, and two fans by which the rice and hulls are blown from the 
huller to the polisher, and then are made to pass repeatedly through the polisher, 
until a suitable finish is obtained. The machine is driven by a Binall electric 



144 AGBl6tft/fTTRAL JOURNAL OF BBlriSH OtrtASA. tlX 1 

motor, and the air system also separates the hulls from the rice. The normal 
procedure is to hull, winnow and polish in one operation, the time required for 
100 grins, of padi being 2 — 3 minutes, but these processes can be carried out 
separately, in order to find the breakage on hulling compared with that on 
polishing, and also to find the amount lost in polishing. The latter method was 
adopted in this investigation, the time of polishing being one minute. The 
broken grains were separated by the hand grader which forms part of the mill- 
ing outfit. It consists of a metal plate, with hemispherical indentations of 
standard diameter (4.5 millimetres), suspended on wires and vibrated by an 
eccentric drive. The broken grains are retained by the plate, which is readily 
removed from its frame. 

Conditions of steeping, steaming and drying were thus standardised as far 
as possible, although of course, the rate of drying varied with the amount of 
sunshine. “ White-belly ” was not found in any sample, so the method of par- 
boiling was effective for all varieties. The parboiled padi was then hulled and 
winnowed, and the breakage due to hulling was measured. The whole grains 
were then polished for one minute, and the breakage and loss in weight duo to 
polishing were fouhd in the same way. Replications of the tests showed that fine 
distinctions of milling quality were not permissible, but the difference between 
the poorest and best was sufficiently large to show up those varieties which are 
likely to give a high breakage on large-scale milling. These differences would 
probably be magnified under factory conditions, since the lowest breakage 
percentages are small compared with those in commercial milling. 

The test is thus of comparative value, and forms a useful adjunct to 
selection work. It is not suggested, however, that an otherwise promising 
variety should be discarded in the early stages of selection purely on account of 
its reaction to this test. By applying the test in the later stages of variety trials, 
when seasonal and environmental variations are being taken into account, it 
should be of value in judging a variety before large scale distribution is carried 
out. In addition to this, it might conceivably be used where strength of grain 
is being considered in breeding work. 

II. Experimental. 

The table of results gives the figures for breakage due to polishing, total 
breakage, length of grain (average of 10 grains hnsked by hand), and the yield 
in lb. from 1,000 plants in the selection tests. The varieties are arranged in 
three classes, long-grain types (over 7.3 mm.), medium-long types (0.9 — 7.3 mm.) 
and medium grain types (below 6.9 mm.). In each class the varieties are 
arranged in order of yield, since this property is the first consideration in 
selection work. Sethi et al. (Indian J. Agr. Sci. Oct. 1937 p. 713) carried out 
milling tests on sin varieties of Indian padi, using 30 lb. samples milled with an 
Englefeerg huller, and they attributed their differences in milling quality to 
seasonal factors existing at the time the respective crops matured^ and to the 
post-harvest operations, such as drying, threshing, etc. In the present investiga- 



Plate v. 



Fig. 1 : — Apparatus for Steaming Padi 




A. MILLING TfcgY ON SIXTY PaJM VabIETIES. 


145 


tioa these factors have been standardised to a great extent, since the plants were 
grown, harvested, threshed and dried under the controlled conditions of selection 
work. The breakages given by Sethi and his colleagues are high in comparison 
with onrs, ranging from- 37 to 55 per cent., due in part to the fact that they 
worked on a semi-large scale, with padi grown under field conditions. 

Figures for loss of weight on polishing are not given in the table, as there 
was very little difference between varieties, the range of figures being between 
10 aDd 12 per cent. This shews, however, that there is an appreciable loss of 
weight on polishing, and the breakage figures demonstrate that nearly all the 
breakage occurs during polishing. 

Table op Results. 


Variety 

Yield : lb. per 
1,000 plants 

1 

Length of 
Grain mm. 

Total 

Breakage % 

Breakage on 
Polishing % 

Long Grain Types (over 

7.3 mm.) 


1 


54—37 | 

110.3 

7.7 

8.5 

7.4 

Padi Berbice 

100.7 

7.4 

12.2 

11.1 

Sue 

95.6 

7.4 

4.7 

4.3 

Jaisingh 

92.9 

1 7.7 

' 6.3 

5.8 

53—37 

88.2 

l 7.5 

| 8.8 

7.7 

D 254 

85.6 

7.4 

2.9 

1.6 

D 259 

85.1 

8.0 

| 11.6 

10.5 

51—37 

84.6 

' 7.5 

| 6.9 

5.9 

52—37 

80.9 

7.6 

11.8 

10.0 

13—37 

80.6 

7.5 

14.1 

10.5 

D 90 

77.9 

7.7 

5.6 

1 5.1 

8eymonr S 

! 76.8 

7.9 

4.8 

4.0 

Nickerie Patna 

75.4 

7.4 

6.3 

5.5 

D 89 

71.9 

7.6 

6.8 

6.1 

D 162 

69 4 

. 7.4- 

5.6 

5.1 

D 221 

67.6 

7.7 

5.7 

3.9 

31—37 

67.5 • 

7.4 

11.1 

9.0 

30—37 

65.1 

' 7.5 

53 ' 

4.3 

Ramjess 

64.6 

7.4 

3.4 1 

2.6 

D 228 

63.7 

, 7.8 | 

9.5 1 

7.8 

D 91 

63.6 

! 7.5 

6.3 

5.5 

Demerara Creole 

61,1 

, 7.6 

4.2 

3.5 

27*— 37 

57.1 

, 7.5 

8.8 

7.6 

No. 76 

56.9 

1 7.6 

5.0 

4.2 

No. 75 

54.7 

i 7.5 • 

5.3 

4.7 

Kalyaman 

54.0 ; 

7.6 

6.2 

5.2 

25—37 

52.5 1 

_ 7.7 

10.9 * 

7.0 


Average for Long-grain types : Total breakage =7.3 (Range 2.9—14.1) 
' Breakage on poli»hing=6.1 (Range 1.6 — 11.1) 







166 AGBICtTI/TUBAJj JoTTENAL ofr BKITISH GTJIAJffA. flK, &. 


* 

Variety 

Yield: lb . 
per 1,000 
plants 

Length of 
Grain mm. 

Total 

Breakage % 

Breakage on 
Polishing % 

Medium-long Grain 

1 

Oi 

CO 

I 

7,3 mm.) 



D 255 

110.2 

7.0 

3.6 

3.1 

D 256 

92.9 

6.9 

3,5 

3.0 

P 115 

86.3 

7.1 

5.3 

5.2 

P 255 

84.2 

7.3 

7.3 

5.3 

P 258 

82.2 

6.9 

6.0 

4.2 

P 116 

73 6 

7.1 

6.3 

5.1 

D 109 

73.4 

7.3 

8.1 

7.1 

29-37 

72.1 

7.3 

6.4 

5.0 

D 92 

70.6 

7.2 

7.0 

5.9 

D 251 

70.5 

7.3 

3.4 

2.8 

D 114 

68.9 

7.1 

5.6 

5.1 

P 88 , 

63 7 ' 

7.3 

7.5 

6.7 

II 7 

61.2 

7.3 

7.1 

1 

5.5 


Averages tor Medium Long-grain types : Tot^l breakage =5.1) (Rangel.3.5 — 7.5) 
Breakag e on p olishin g 5 ^!.!) (Range 2.8 — 7 .1) 


Variety 

Yield : lb. 
per 1,000 
plants 

Length of 
Grain mm. 

Total 

Breakage % 

1 

I Breakage on 

1 Polishing % 

i 

Medium Gram Types 

(below 6.9 

mm.) 



P 257 

106 2 

6.3 1 

2.4 

1.7 

17-37 

89.8 

6.7 

3.5 

3.1 

Unity 

88.3 

| 6.5 

1.1 

0.8 

19-37 

82.6 

! 6.6 

4.0 

2.7 

15-37 

82,4 

6.7 

3.9 

2.9 

P 247 

81.3 

6.5 

5.1 

3.6 

P 108 

76.0 

6.6 

1.6 

1.0 

23-37 

75.7 

6.6 

7.0 

3.9 

D 250 

73.9 

6.6 

3.4 

1.8 

18-37 

73.1 

6.6 

5.1 

3.5 

P 246 

71.6 

6.8 

3.8 

3.4 

P 99 

70.9 

6.3 

4.9 

3.4 

P 97B 

69.7 

6.6 

3.7 

2.2 

P 94 

69.6 

6.6 

2.6 

2.2 

P 193 

69.1 

6.8 

3.1 

1.7 

P 110 

68.5 

6.8 

2.0 

1.7 

Bine Stick 

62.6 

6.5 

1.6 

1.1 

No. 79 

61.6 

6.5 

1.2 

0.7 

P 261 

54.1 

6.3 

3.6 

3.1 

i P 262 

45.5 

6.6 

4.2 

3.9 


Averages for Medium-grain types : Total breakage—3.4 (Range 1.1 — 7.0) 

Breakage on polishing— 2,4 (Range 0,7— 3.9) 







Plate vi, 



Fig 2 Experimental Mill. 

Left: Holier. Centre * Polisher. Riyht: Grader. 




A MILLING TEST ON SIXTY PAW V ABIE TIBS. i 6? 

III. Discussion. 

It is striking that about 90 per cent, of the breakage and a loss in weight of 
over 10 per cent, occur daring polishing. This shows the value of pure line 
padi, since variation ill size of grain and in colour of cuticle would probably 
make longer polishing necessary. On the other hand there were considerable 
differences between varieties in the colour of the unpolished rice grains, and 
thus it would be possible to cut down the time of polishing when working on a 
commercial soale with certain varieties. This point is important in the 
economics of rice milling, as it seriously affects both breakage and recovery. 

As would be expected, the long-grain types gave on the average a higher 
breakage than medium-long, the medium grains being the best of the three 
classes. It is somewhat surprising to find that the shape of grain did not always 
prove to be a dominant factor, since Demerara Creole, a scimitar-shaped grain, 
gave a low breakage for its class. 

Of the long-grain varieties, Sue, Seymour S, D 254, Ramjess and Demerara 
Creole appear to give the hardest grains on parboiling, but they are not marked- 
ly superior to several others, such as D 90, D 162, D 221, 30-37, No. 76 and No. 
75, which show only a slightly higher breakage. It is difficult to pick out the 
best variety as regards milling properties, but several gave high breakages, which 
leads to considerable doubt as to their suitability for commercial extension. Of 
these, Padi Berbice, 13 — 37, D 259, 52 — 37 and 31 — 37 all gave over 10 per cent, 
breakage. 

On the whole, there is not much to choose between the medium-long varieties. 
Rven D 88, with 7.5 per cent, breakage, is not greatly inferior to D 251, which 
gave the lowest figure (3.4) of this class. Other varietal properties would 
probably assume more importance in the selection and breeding work in this 
class. The medium-grain padis, with an average breakage of 3.4 per cent, 
includes several varieties which repeatedly gave practically no breakage, since 
figures under 2 per cent, could be accounted for by bird damage and insect attack. 
From the miller’s point of view, it would be preferable to concentrate on types 
with grain length below 6.9 mm., but of course, market requirements and other 
economic and biological factors might outweigh this consideration. 

Undoubtedly, the most important factor in breakage is the rate of drying 
both in the field and on the factory drying floor. In our preliminary work we 
had considerable difficulty in ensuring that drying would take place at a reason- 
able rate without being too rapid. The effect of too rapid drying will far 
outbalance the differences between varieties which have been noted here, but it 
should be remembered that those varieties which showed up badly in this test, 
did so under conditions which were nearly ideal. It seems reasonable to argue, 
therefore, that varieties which gave comparatively high breakages would be 
difficult to handle under factory conditions, and thus the test would be of value 
in eliminating unsuitable varieties. On the other hand, it does not follow that 
every variety which is suitable on these standards will retain its plaoe when 





AafeicmAtifcAt JOt&hAL o* Bfeitasb cAtju&a. 


tlX,! 

subjected to large-scale milling. In our first tests the rate of drying was too 
high for most varieties, but one or two seem to withstand even severe conditions, 
and further work along this line will be carried out in order to find which varie- 
ties can be dried rapidly without excessive breakage. 

Acknowledgment. 

This investigation was suggested by Capt. F. Burnett, Deputy Director of 
Agriculture, and thanks are due to him, and to Mr. P. A. Cban-Ohoong, Assistant 
Plant Breeder, for the padi samples and for the yield and grain-length figures. 



Plate vii, 



Fig. 3:— Close View of Grader. 





SELECTED ARTICLE 


THE CULTIVATION OF CAJANUS CAJAN AND THE 
METHODS OF PREPARING MARKETABLE DHAL*. 

BY 

P, M. GAYWALA, M.Ag„ (Bombay) 

Demonstrator in Cultivation , Farm School, Peradeniya. 


Cajanus cajan ( —C. indicus) is considered to be one of the most promising 
legumes at the present time. It is one of the favourite crops of the average 
village cultivator for a variety of reasons. The Indian farmer has recognised 
its value in the light of his accumulated experience extending over several 
centuries. The scientific study of agricultural problems during recent years has 
confirmed its recognition by the cultivator. It occupies a predominating 
position among the pulse crops of India and is used as a restorative, rotational 
or mixed crop. 

Prom the point of view of keeping the soil in fertile condition in dry and 
arid tracts, there is hardly a leguminous crop that can stand comparison with it. 
Being a drought resistant crop, it grows successfully in tracts receiving annual 
rainfall of 25 to 30 inches or even less. It has been known to have grown 
successfully in some dry seasons when other crops have failed. It has a deeply 
peaetrating root system which enables it to open up any hard set soil to a great 
depth thus aerating the soil and bringing it to a much finer state of physical con* 
dition for the subsequent crops. Throughout its growing period and particularly 
during the later stage it sheds a large amount of leafy material which definitely 
enriches the soil in valuable organic matter. Like other leguminous crops, it 
also fixes atmospheric nitrogen in the soil. From the economic point of view, 
the crop possesses some commendable features. The plant yields seed which 
affords a nutritious article of food. The leaves, the husk of pods and the seed 
ooats, which are all by-products of the crop, are utilized as excellent feeding 
stuffs for the milch and draft cattle of the farmer. The stalks supply him his 
domestic requirements of fuel. The cultivator usually sells the surplus grain 
for which he finds a ready market. The crop has therefore many desirable 
features in its favour, viz., it furnishes food for the farmer’s family and cattle, 
provides fnel, and helps to maintain the fertility of the soil while* it is also a 
money crop. 

•Reprinted from the *' Tropical Agriculturist " of Ceylon, Yol. XC, No. 4, Apnl lWb, 



170 


AGRICULTURAL JOURNAL Of BRITISH GUIANA, 


[IX, 3, 


The pulse is used in a variety of ways but its ohief use is in its split form as 
dhal Dhal contains as high as 18 to 20 per cent, proteins and is therefore of 
definite value to a vegetarian population. The tender pods of this crop are 
extensively used as a vegetable in the same manner as garden peas. An Indian 
cultivator living near a market sells the first part of his crop in the form of 
green vegetable pods and allows the pods which form later to mature for the 
production of seed. 

The plant has further uses. During recent years it is being developed, 
particularly in the United States of America, as a leguminous fodder crop and 
in this respect is likely to rival lucerne in importance. It does not require such 
careful management as lucerne. Being a drought resistant and hardy crop it 
grows well in any soil under adverse conditions with little attention. It 
matures for fodder comparatively rapidly and is capable of being utilized as a 
perennial fodder crop. Live stock and poultry relish the crop. It has also 
been recommended as a green manure crop. According to leaflet No. 14 of the 
Ceylon Department of Agriculture it may be grown as a green manure crop 
interplanted with young rubber and coconuts in tracts receiving less than 100 
inches rainfall. However, as a green manure crop for annual crops it does not 
compare favourably with other well known green manure crops on account of 
the comparatively slow habit of growth and the large proportion of woody 
material in the plant. It is also grown as a shade crop, cover crop, and 
occasionally a wind-break hedge plant. In Assam, for example, it is grown as 
a border crop round sugar oane fields more for the protection of the cane crop 
than for the yield of its seeds. In such cases the dry stalks serve the purpose 
of a much needed fuel in boiling the cane juice. 

Varieties. 

The plant is known to have a large number of varieties with slightly 
different characters, growing under varying conditions in many parts of India. 
The recent survey of the varieties of this plant by the Imperial Economic 
Botanist at Pusa (Scientific Reports of the Agricultural Research Institute, Pnsa, 
1928-29, page 21) shows that the number of distinct types obtained was 107 in- 
dicating great variations in height, habit of growth, the time of maturity, colour 
of flower, colour and shape of pods, and the size, colour and shape of seeds. The 
varieties, however, can be subdivided into main groups. The first comprises the 
peieunial type which assumes a tree-like appearance and is allowed to grow for 
more than a year. From the point of view of yield of seed, this variety yields 
a fairly good first crop but the yield in subsequent years falls considerably. 
This type is used more as a shade, fodder, cover, or hedge plant than for seed. 
The small or annual type is mostly grown as a field crop for its seed. The size, 

t pe and colour of seed vary in different varieties. The white seeded variety 
ich is grown in Gujarat, Western India, yields a very fine quality of dhal 
fetching the best market price. The red or the brown seeded variety does not 
grow well in the heavy black cotton soils of Gujarat and is mostly confiped tp 
the lighter type of soils soptfi pf Bombay, 



THB CULTIVATION OF CAJANUS CAJAN. 


171 


Soil and Climatic Requirements. 

Cajanus cajan is grown mostly in mixture with a large variety of crops 
under a wide range of soil and climatic conditions. This fact indicates that the 
plant is quite capable of adapting itself to widely variable conditions. Under 
dry conditions'it comes to maturity fairly quickly. Under humid conditions as 
would be expected the crop tends to produce luxuriant vegetative growth. 
Cloudy weather and rain at the flowering time causes defective fertilization and 
the pod-caterpillar appears on the crop damaging the growing pods. Stagnant 
water in fields is definitely harmful to the crop. 

The wet zone of Ceylon is rather unsuited to the successful cultivation of 
this crop for seed production. The climate is likely to prove too humid and the 
flewering is liable to be affected. In the dry zones subject to one monsoon only 
and where the rain has almost ceased by the time the plants come into flower, 
the crop would naturally grow well. Moreover, there is every possibility of 
finding a strain suitable for any given local conditions from among the large 
number of varieties growing under a wide range of climatic conditions in 
India. If the aim is not the production of seed, the plant may be grown in the 
wet zone and will produce luxuriant vegetative growth for purposes of fodder, 
shade, cover, hedges or wind-breaks. 

Methods of Cultivation. 

In India the Cajanus cajan crop is usually grown as a mixed crop. It is 
sown in widely spaced lines as a subordinate mixture with other crop or crops 
of a shorter growing period, such as sorghum, maize, bulrush millet, other 
millets, gingelly, ground-nuts, &c. These intervening crops, being of a shorter 
duration than Cajanus rajan, are ready for harvesting first. The Cajanus cajan 
achieves its full growth after the maturity or removal of this intervening crop 
and is then able to utilize all the additional space made available between the 
rows. * .• 

Because of the fact that it is raised as a mixed crop, the soils available for 
this crop naturally vary with the requirements of its accompanying main crop. 
For example, with sorghum it will occupy a heavier clay loam type of soil ; 
with millets, groundnut and gingelly it will occupy a lighter type of loam to 
sandy loam soils. Usually it does not require manures but if grown on a newly 
opened or well manured land, growth is luxuriant. As with any other legum- 
inous crop the soil for this crop should not be deficient in lime. The character of 
preparatory tillage will be determined by the requirements of its associated crop. 
In India it is usually sown at the commencement of the south-west monsoon in 
June or early in July and is ready for harvesting by Feb^pary or March. 
The other crops grown in association are usually harvested by the first week of 
October. The period from October to March is more or less dry and rainless. 
The crop does not require any irrigation during this long dry period because it 
is able to draw its own moisture requirements from lower depths with the help 
of its deeply penetrating root system. 



172 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 3. 

In a common and typical form of mixture Cajanw cajan occupies every 
fourth row of the mixed crop which is either drilled by a special attachment to 
the oountry plough called Moffan or is dibbled behind the country plough in a 
line just opened by it. The Cajanua cojan will thus be in rows 4 to 6 feet 
apart depending upon the type of its associated crop and the spacing given to it. 
The seed rate with this type of mixture varies from 1$ to 3 lb. per acre. In 
the case of an unraixed Cajanus crop, the seed rate would amount to about 
8 lb. per acre. In South India where it is sometimes grown mixed with 
gronndnuts, the distance allowed between the two rows of Vajanus eajan is 
10 to 23 feet. The object of keeping it so wide apart is to keep the groundnuts 
as far as possible free from shade. The seed rate in this case is naturally 
very low and depends upon the actual spacing. 

After germination is completed the plants have to be thinned in the 
rows to a space of about a foot apart in light soils. In good and deep soils 
spacing may be done at 2 feet apart. 

During the first 4 to 6 weeks, the crop shares the useful intercultivation 
given to the main crop. The crop is theD usually allowed to take its own 
course. There is a belief in India that the more this crop is trampled when 
the main crop is harvested, the greater will be the subsequent development of 
branches, flowers and pods. When grown with groundnut in South India, the 
soil has to be dug over for removing the groundnut and this serves the purpose 
of a final cultivation without extra cost. If seed production is the object, the 
crop is allowed to remain standing in the field till the pods dry on the plants. 

When it is used as a perennial crop, the branches are cut off for feeding 
cattle whenever required or at regular intervals. At the close of the season, 
the plants are pruned to about 2 feet above the ground. With the advent of 
the new season’s rain, *he pruned plants will start growing again. Thus the 
crop can be made to yield a large amount of leafy material in humid tracts for 
3 to 5 years. It is, however, equally easy to renew the sowings every year. 

Harvesting and Threshing. 

The crop is harvested by cutting the whole plant close to the ground by 
means of a sharp sickle. The actual treatment of the plants after they are cut 
depends upon the prevailing local conditions. Where there is risk of damage 
by rains or by thieves, the plants are tied into small bundles soon after they 
are cut and carted to the threshing floor. Bundles are then allowed to 
remain there for a few days till the green leaves left on the plants completely 
dry off and the ripe pods open slightly. If the possibility of damage by rain 
or by thieves does not arise, • the harvested plants are collected and left in 
the field for a day or two till they are fairly dry and then carted to the 
threlhing floor early in the morning to avoid shedding of seeds fropa the 




THB CULTIVATION OF CAJANUS CAJAN, 


173 


The threshing is usually done by vigorously shaking the dry plants. A 
good many pods and seeds with leaves are thrown out. Those that do not 
drop by shaking are finally beaten with strong bamboos or wooden flails. 
When everything has dropped from stalks the material is farther beaten by 
sticks or trampled under the feet of bullocks which completely separates the 
grain. The grains are further cleaned from the chaff by subsequent winnowing. 
The chaff so separated is a good feeding stuff for draft cattle. The stocks are 
mostly used as a fuel. Thin or straight stalks or branches are used for roofing 
or for making the sides of the bullock carts. 

Yields. 

As a fourth row mixture, the yield of seed ranges from 300 to 600 lb. 
per acre depending on the type of mixture adopted and the soil and climatic 
conditions under which it is grown. A bushel of seed usually weighs 56 lb. 

Method op Marketing in India. 

The seed produced by village cultivators is usually brought by them in 
cart loads to primary markets located in small towns near by. Here the 
professional dhal-makers locally known as golas buy the produce with a view 
to making dhal out of it. This professional class of golas is found in most of 
the small towns all over India. To them dhal-making is a fairly profitable 
small scale industry extending over the greater part of the year. They are 
a class of people with limited moans and work with the small hand-operated 
splitting mills run by hired labour. The methods of milling slightly vary in 
different districts. A few enterprising golas beep several such mills and 
work with a larger labour force during periods of demand. Large scale modern 
mills operated by mechanical power have not been erected to any appreciable 
extent chiefly because the people engaged in this industry are of limited means 
and also because most of the villagers are producers as well as consumers of 
dhal. A few power mills are to be seen in some large towns. Some of the 
cultivators who appreciate the value of home-tfiade products make their dhal 
from their own farm produce. To them the necessity for selling the grain to 
golas and later buying the dhal from them does not exist. The dhal produced 
by the cultivators themselves is of good quality because of the great care 
exercised by them. Most of the dhal produced by the cultivator is for the 
use of his own family and only the small surplus is disposed of. As will be 
seen later, the process of dhal-making is quite simple, and every cultivator 
can prepare his requirement with little effort unless he has a more important 
call upon his time. 

Preparation of Dhal. 

The particular method of preparing dhal adopted has 1 Sn important 
bearing upon the final quality of the commercial product. It may therefore 
"'fee useful to djscuBS flrBt the points which decide the quality of dbal. Dhal is 
chiefly used as a food in boiled form. A good quality of dhal should be easily 



174 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 3. 

and quickly reduced by boiling to a homogenous semi-liquid mass. After 
boiling it should not continue to retain its original form or shape and should 
not show any unbroken hard pieces. If the dhal becomes soft in a reasonably 
short period of boiling, the flavour and taste of the cooked product is 
better than if boiled for a long time. This quality of softening after briefc 
cooking should be retained during the storage period ; this is the second 
important consideration of quality. Any sample of dhal, therefore, which 
cooks soft quickly and retains this quality during a fairly long period of 
storage is regarded as of good quality. 

There are two well defined methods of preparing dhal in India. Each is 
practised under certain local conditions and has its own advantages and 
disadvantages. 

The first is the dry method which is chiefly used in Gujarat and parts of 
Northern India. The dhal obtained by this method softens rapidly on cooking 
and the resulting flavour is very good. This method of preparation is costly 
and the proportion of broken dhal is comparatively more. The dhal obtained 
by this process is of perfect shape of a half -moon. It realizes a very good 
price in the market. 

The second is the wet method in which water is freely made use of. 
Something like controlled malting takes place. The resulting dhal is hard to 
cook after a short period of storage and is not then fully reduced to a 
homogenous semi-liquid mass even after prolonged boiling. The flavour is not 
So good as in the dry method. The method has the advantage of cheapness. 
Another advantage in its favour is that the proportion of broken dhal is very 
small and therefore the percentage of dhal recovered by this process is much 
greater. The dhal obtained has a semi-round shape depressed in the centre. 
This process is extensively used in South India extending up to Bombay Deccan 
with slight local modifications. 

Both processes require ample sunshine for thorough drying of the seed 
preparatory to dhal making. Therefore the availability of bright sunny days 
is the first important essential for successful dhal-making. Such conditions 
obtain in the dry zones of Ceylon and thus make possible the creation of a 
small village industry providing occupation throughout most of the year. 

The splitting mill used in both of the above methods is a mill with two 
circular stones, one of which rotates round an axle fixed perpendicularly at the 
centre of the lower or bottom stone. The axle passes through the upper stone 
which is provided with a centre hole through which the grains are fed into the 
mill. There is another small hole near the circumference of this upper stone 
where a strong peg is fixed. By means of this peg the upper stone is made to 
rptiite round the axle. The pulse seed is thereby split up into two halves or 
cotyledons and tbe seed coat is separated, The pulse seeds are ted through the 



TOT CULTIVATION OB' CAJANTTS CAJAS. 


175 


hole in the centre and the split dhal is collected below ronnd the stone. The 
stone mill used in Gujarat generally weighs about 120 to 150 lb, and costs about 
Bs. 15 to 25 depending on the quality of stone used. 

In some places a mill of larger sise is used but has to be rotated by two 
persons working simultaneously. It is provided with two strong pegs fitted in 
two boles at opposite points on the upper stone near the circumference. 

Dry Method of Making Dhal. 

This process can be conveniently divided into the following seven stages 

(1) Preliminary sun-drying. — The seeds are exposed to hot sunshine for 
three to four days. If the temperature is below 90°F., drying may have to be 
prolonged for a longer period. 

(2) Preliminary and partial splitting of grains. — This is usually done 
at noon. The grains are taken from the drying place and they are fed to the 
splitting stone mill in a hot condition. The grains are fed rapidly in large 
quantities at a time. The object is to get the seed coat pressed and effect some 
cracking of the seed coat while the seeds are moving in a hot condition between 
the stones. Along with cracking of the seed coat, about half the seeds split 
into cotyledons but their coats are not removed. The partially split seeds with 
cracked seed coats at this stage of the process are known as dol. The above two 
stages of the process can be carried out soon after bringing the produce from the 
fields if desired, or at any other suitable time. 

(3) Treating the dol with vegetable oil and storing it. — The dol so 
obtained is not usually made into the final dhal immediately. It is treated 
with a small quantity of vegetable oil at the rate of about 2 lb. per 100 pounds 
of dol , and stored for varying periods. If the storage period iB to extend for 
more than a month castor oil is used ; gingelly oil being used if the storage 
period is less than a month. Storing of dol treated with oil for at least a fort* 
night is considered necessary. The ohief object pf treating dol with oil and 
storing it for some time is to allow the slightly cracked seed coat of the pulse 
to absorb the oil making the seed coat soft and thus assisting considerably in 
the final splitting of the pulse into dhal and the removal of the seed coat from 
the split dhal. The treated material should remain oily during the entire period 
of storage. The variation in the storage period offers an opportunity to distri- 
bute the dhal making business over a longer period of the year so that it can 
be done at convenient times. 

i 

(4) Second sun-drying. — After the storage period is over, the oil-treated 
and stored dol is again exposed to sunshine for two to five days depending upon 
the prevailing temperature. 

(5) Final splitting. This is also done at noon. The material is fed to 
the same stpne mill, preferably in a warm condition at slower rate and in 
smaller quantities than during the preliminary splitting. During the course of 



170 AGRICULTURAL JOURNAL OP BRITISH GTJtANA. [IX, 3. 

this operation the seed coats will separate, and a large portion of the nnsplit 
material will also be split up. Daring splitting the mill mast move compara- 
tively slowly as otherwise a great proportion of the dhal is likely to be broken up. 

(6) Sieving mid winnowing . — The split dhal iB then separated and cleaned 
from the seed coat by sieving and winnowing. The small broken pieees 
are also separated as far as possible. 

(7) Treating finally with vegetable oil . — The dhal is then finally treated 
with castor or gingelly oil at the rate of about 2£ lb. per 100 lb. of dhal and is 
ready for sale. The final oil treatment is intended to preserve the quality of 
dhal, prevent insect attack and make it of attractive appearance. 

This method of dhal-making is rather expensive because of the nse of 
vegetable oil at two stages, and the extra labour required in double splitting. 
Moreover, the proportion of broken dhal is much higher. From 100 lb. of seed 
about 66 lb. of clean good quality dhal is obtainable. The rest is broken 
material and the seed coats. 

t 

The outer covers of the seed in admixture with the small broken pieoes of 
dhal obtained^ a by-product in dhal-making is known under the name of 
chuni throughout India, It is a favourite concentrated foodstuff for dairy cows. 

Wet Method of* Making Dhal. 

The seed collected by professional dhal makers is allowed to soak in water 
for about six hours either in tubs or in well constructed vats. The free water 
is then removed or drained away. At this stage, fine, well sieved earth prefer- 
ably of the red laterite type is added at the rate of about 5 lb. per 100 lb, grain and 
well mixed. The mixture of soaked grain and moist earth is heaped up and 
kept in that condition for the night. Next morning, the heap is broken up and 
the material exposed to the sun for drying. The drying continues for a day or 
two according to the temperature. After thorough drying the seeds are again 
mixed up with a thin turbid mixture of red soil and water and heaped up for 
the night. Next morning they are removed and thoroughly dried. They are 
then sieved and winnowed to remove the earth and other impurities. The seeds 
are finally split into halves in the stone mill. 

Cultivators who prepare their own dhal adopt a slightly modified method 
which is more laborious and takes more time, but the dhal obtained is of some- 
what superior quality. Instead of soaking his seed in water the cultivator 
prepares a thin mixture of red laterite soil and water and applies this earth 
solution to his seed at repeated intervals of about an hour throughout the day. 
Each time the earth solution is well mixed up with the seed by repeatedly 
timping over the heap. By this method the seeds do not absorb moisture in free 
water but the absorption of moisture is being effected gradually in several 
stages. The heap remains undisturbed throughout the night. In the morning 
the seedis exposed to ih# sun for drying and then finally split np into dhal. 



TfiB CULTIVATION OF CAJANUS CAJAN. 


177 


The professional dbal makers allow the seeds to absorb a larger quantity of 
moisture and the seeds swell considerably. On drying such seed the shrinkage 
is great and therefore the resulting dhal assumes a marked depression in the 
oentre. In the cultivator’s method, as the soaking is gradual and according to 
requirements, the resulting &hal does not have so prominent a depression in the 
centre. 

By the web method, 100 lb. of seed yield about 80 lb. of marketable dhal. 
The breakage of dhal is low. The object of wetting and drying is of course, to 
produce a contracting and expanding action on the seed coat which, as a result, 
offers much less resistance when the seeds are being split in the mill. 

Concluding Remarks. 

A close observation and study of the conditions under which Cajanun 
cajan is cultivated in India indicates that some of the varieties of this plant are 
capable of successful cultivation for seed production in the dry parts of Ceylon. 
The small scale processes of dhal-making described above are fairly simple and 
do not require expensive outfits. The requisite number of dry sunny days are 
available in the dry zones for the preparation of dhal. The local consumption 
of dhal in Ceylon is considerable. Under the circumstances, it is quite possible 
with some effort and attention to produce good quality dhal for local consump- 
tion. The crop itself is likely to prove an important rotational crop or an 
appropriate mixed crop in the village agriculture of this country, while the 
preparation of dhal offers an opportunity of being taken up as a new and 
profitable cottage industry in the dry zone. 



REPORT, 


The fifteenth meeting of the advisory board of 

AGRICULTURE. 


Present. 


The Director of Agriculture 

The Deputy Director of Agriculture (ag.) 

Hon. F. J. Seaford, O.B.E. 

„ Peer Bacchus 

,, J. W. Jackson ^ 

„ R. E. Brassington 
Mr. W. H. Richards 
Mr. S. Andries 

' with 

Capt. J. F. Irving, M.C. 

Absent. 


Mr. R. B. Hunter. 


Chairman 


Members 


Secretary 

Member 


An excuse for non-attendance was tendered for Mr. R. B. Hunter. 

The minutes of the last meeting held on March 21, 1938, which had 
previously been circulated, were confirmed. 

The Chairman referred to the following matters arising out of the minutes : 

(1) Cattle Branding Ordinance. No further communication had been 
received from Government but the intention so far as he knew was not to 
proceed with the amendments. Hon. F. J. Seaford said that enquiries had 
recently been made by the Rupununi ranchers as to the placing of brands on 
animals in such a way as not to prejudice the value of the hides and Govern- 
ment had been written regarding the proposed amendments. He asked that 
if the matter were again referred to the Board it should receive early 
attention. Hon. Peer Bacchus remarked that from his experience a large brand 
was useful in the country districts as it enabled owners to recognise their 
animals from a distance. Members thought that changes as regards size and 
position of brands might apply to Rupununi cattle only at first. 

(2) Berbice Exhibition. It was proposed to make arrangements for 
holding the postponed show next year. 

(3) Glasgow Exhibition. The Department had forwarded agricultural 
products in co-operation with the Departments of Forestry and Lands & Mines. 



REPORT. 


179 


(4) La Belle Alliance . The Director of Public Works was proceeding with 
the drainage of the area and a start was being made with the sand reef for 
buildings and stables, etc* 

(5) Government Veterinary Surgeon . Consequent on the retirement of 
Major T. Bone, Mr. H. A. Fraser had been appointed to act in his place. 

(6) Reduction on Railway Freights . The Deputy Director had gone into 
the matter with the Managing Director, Transport Board, who had supplied a 
tariff with all the information on the subject. 

Unfortunately, the Managing Director had stated that he could hold out 
little hope of any decrease ; rather there was every chance in view of the 
increased cost of wages, etc., of the possibility of freight charges having to be 
increased. It was unanimously agreed that Hon. Peer Bacchus and the 
Secretary should see the Managing Director on the subject, 

Coffee Committee's Report. The Chairman said that the report of the Coffee 
Committee had been submitted to Government, but as this was not yet 
published he was not in a position to discuss the matter at present. 

Fine-curing of Tobacco. The Chairman reported on the results that had 
been obtained in connection with the tobacco flue-curing experiment. About 
£ of an acre had been planted at Sophia and a small flue-barn had been built. 
The results obtained had been fairly satisfactory and the two local tobacco 
factories had stated that they were prepared to buy a limited quantity of local 
tobacco but would not commit themselves beyond a certain figure, as this 
would depend entirely on the quality of the article produced. It was essential, 
however, that whatever is grown must be properly cured, packed, etc., and as 
there are many defects still to be overcome — although the local factories have 
stated that the leaf so far supplied is the very best they have seen locally — the 
Secretary of State had been approached for assistance from the Colonial 
Development Fund Advisory Committee to obtain the services of an expert in 
flue-curing methods and barn construction. 'Jhis officer would be of great 
assistance in the proper construction of barns and would be available for 
instructions in the principles, practices and technical aspects of cqring tobacco* 
The Board were unanimously of the opinion that the project, which appeared 
an encouraging one for the creation of a minor industry, should be helped in 
every way possible although the question of offsetting the revenue loss through 
customs duties which was raised by Hon. F. J. Seaford, would, no doubt, 
have to be considered at a later date. 

4 

Fruit c£ Vegetable Conference. The Chairman stated in connection with 
the Fruit and Vegetable Council Meeting at Trinidad, he had introduced a 
motion recommending that the intercolonial fruit and vegetable trade be care* 
fully investigated by the Governments concerned, both from* the commercial 
as well as the quarantine aspects, with a view to its proper organisation and 
control. A* copy of the resolution and the related correspondence had been 



1#6 4 Agricultural journal of britisr guiana, [IX, 3. 

forwarded by Government to the Georgetown Chamber of Commerce and this 
body had decided to raise the question at the next meeting of the Associated 
Chambers of Commerce to be held shortly in Trinidad. 

Bananas . The Chairman said that he regretted to have to report adversely 
on the progress of the banana plots both at Middlesex and Supply. The losses 
sustained from Panama Disease at Middlesex to date were approximately 30% 
of the stools, while Leaf Spot disease was still very active in spite of spraying. 
Of the bunches reaped to date only a small percentage wore of the 44 count 
bunch’ 1 class i.c., 9 hands ; 7-hand bunches were fairly common. Mr. Richards 
asked what was the amount placed on the estimate for the work and was 
informed that $750 had been allocated this year. He said he considered that 
matters had gone far enough and the plots should be immediately closed down, 
as it was a pure waste of money to go on further with the experiments. The 
Chairman said he hardly liked to suggest this step as false statements were 
being made that the Department of Agriculture did not want to see a banana 
industry, although the whole subject had been fully ventilated in the Legis- 
lative Council. It was agreed that a memo, should be published on the results 
so far obtained and that Government should be informed that in the opinion of 
the Board further expenditure did not seem justified. 

Shipment of Limes. The Chairman reported that recently a shipment of 
20 crates (about 3,200 lruits) of green limes had been made to Canada for which 
tbe sum of $24.58 had been received. The expenses including freight, cost of 
crates, etc., had amounted to $19.24. The small balance would leave little 
actual profit to the North-West grower on whose behalt this effort was made. 

Anthrax. The Chairman reported that he regretted to announce that 
Anthrax had broken out in the County of Borbice, at Pins. Bohemia, 
Susannah and Hermitage, as well as at Pins. Palmyra and Seawell. Every 
effort- was being made by the Department in collaboration with the Police 
authorities to control the spread. The Medical Department also was involved 
and had taken steps to prohibit the sale of milk from the infected areas. He 
feared that the Veterinary Preventive Measures Vote would be inadequate as 
special constables had to be employed to control cattle movements, but this 
could not be helped under the circumstances. 

Livestock . In connection with other Livestock matters, the Chairman 
mentioned that arrangements had been made for a bull pen to be erected 
shortly at Whim, Corentyne, and he also hoped to place some pure bred 
poultry and a purebred boar there. He further stated that as export of 
poultry and eggs had been taking place from Berbice to Trinidad by the small 
Dutch steamers calling at Springlands and New Amsterdam, the time seemed 
opportune tor creating additional interest in poultry rearing. He was glad to 
announce that it was the wish of a number of interested persons to resuscitate 
me Poultry Association and a meeting was being held in this connection on 
August 12, at 4.30 p.m. to which he welcomed members of the Board. This 
was considered a step in the right direction. 





m 

Arrival of Rice Mill Engineer . The Chairman referred to the future 
visit of Mr. Parker, rice mill expert, whose experience in connection with Rice 
Mills elsewhere should prove of great benefit to the rice industry in this 
Colony. 

District Agricultural Committees. The Chairman sought the advice of 
the Board as to whether the need any longer existed for District Agricultural 
Committees, of which there were two, in view of the fact that there was now a 
properly constituted Advisory Board of Agriculture, as it meant considerable 
duplication of work. Several members who served on such District 
Agricultural Committees agreed that they no longer served any useful 
purpose. The leeling was that they should be discontinued, but 
the question of publishing the minutes of the Board might be re-opened. 

Information for Colonial Empire Marketing Board. The Chairman in- 
formed the Board that notes had been prepared and submitted to Government 
for the Colonial Empire Marketing Board on the various products of the Colony 
for which remunerative markets were argently required, e.g. y coffee, plantains and 
by-products, cassava and by-products. The position in regard to rice had also 
been dealt with and the need for help in the utilization and disposal of fruit pro- 
ducts, juices, etc., had also been emphasised. 

Economic Survey of Cane Farming . Certain figures in an article published 
in the Agricultural Journal , by Mr. H. D. Huggins in connection with cane 
farmers’ yields were questioned by the Hon. B. E. Brassington who considered 
that the results shown were too high. The Hon. F. J. Seaford said it was possi- 
ble that the figures were a misprint. Mr. Huggins who was present by invitation 
said he considered the figures were substantially correct from information ob 
tained by the survey method direct from the farmers, but he would go over 
them with a view to making any corrections if necessary. 

Malva fibre . Attention was called to a note winch appeared in the u Daily 
Argosy” about Malva fibre in which it was stated that the Department of Agri- 
culture had put a stop to a possible successful enterprise in 1929. 

The Chairman stated that the early records of the Department showed that 
interest had been taken in Malva fibre for some time prior to 1929 and that this 
particular plant — Malachra capitata — had been tried out commercially in many 
countries, notably India, but it had been given up as hopeless. The following 
note by Sir John Harrison in 1925 setting out the position was then read; — 

44 The reasons why Malachra fibre has not been developed commercially 
are simple ; (a) low yield of fibre from the stems j (b) the great difficulty of 
separating tho commercial fibre from the stems by retting and beating. The 
beating has to be done by hand, no machine having been invented for this pur- 
pose. 

44 I have recently had samples of Malachra fibre prepared at the Botanic Gar- 
dens from pitots growing at Sophia Station, The yield of clean fibre was rather 



18& * AGRICULTURAL JOURNAL OP BRITISH GUlAltA. [iX, 3. 

less than 3 per cent, of the weight of green stalks. The cost of gathering the 
stalks, retting them and separating the fibre by hand labour was somewhat oyer 
$708 per ton of the fibre obtained. 

“Personally, I fail to perceive that we are missing anything beneficial to the 
Colony by not undertaking the commercial exploitation of a fibre product the 
production costs of which are $708 per ton in British Guiana and which issaleable 
in London at £60.” 

Since that minute was written by Sir John, further trials had been made 
by the Department but results were not such as to justify immediate commercial 
exploitation. The plant occurs wild in the Colony, but under cultivation, even 
when thickly seeded, does not establish itself in an even stand, while the stalks 
produced are of varying lengths and inclined to branch. The files show that a 
certain individual in 1929-30 approached Government with proposals covering 
the cultivation of 100 acres, using as a basis of his yield figures the returns from 
65 selected plants. It was explained to him that it would be very unwise to 
base conclusions on such a small number of plants and that before embarking 
on an extensive layout, he should arrange to cultivate say five acres under the 
aegis of the Department of Agriculture. Government approved of this and the 
individual .was so informed. The Agricultural Officer in the North West District 
was instructed to co-operate and give every possible assistance and advice to the 
venture but the person concerned allowed the matter to slide and took no action. 

The Board agreed that this explanation should be recorded in the minutes. 

The meeting then terminated. 



Note* 


Padi and Riee Production in India and Burma. — In order to appreciate 
and to make a comparison of the acreages, etc., under padi cultivation in India 
and Burma with this Colony, the following is a short pr6cis of a report taken 
from “ Agriculture and Animal Husbandry in India, 1935-36 ”, 

Padi occupies about 35 per cent, of total cultivated area in India and in 
1935-36 the estimated area was 81,841,000 acres producing 27,902,000 tons of 
rice. Rico accounted for ninety-one per cent, of the total quantity of food- 
grains and flour exported during 1935-36, In 1935-36 the production in India 
proper was 22,843,000 tons and in Burma 5,018,000 and the exports were 191,000 
tons for India proper and 1,213,000 tons for Burma. The exportable surplus is 
derived almost entirely from Burma. Burma was responsible for eighty-six per 
cent, of the total tonnage of rice shipped overseas in 1935-36. In British Guiana 
(1936 census) 62,856 acres were reaped, producing 36,348 tons of rice, whilst the 
total rice exports for the same period were 20,559 tons. 

One of the main activities of the provincial departments of agriculture in 
India and Burma with regard to rice is the distribution of improved strains to 
the cultivators, the total area under improved varieties being 3,667,097 acres in 
1935-36. Rico research is now being conducted on a wider scale than ever, 
chiefly as the result of finances provided by the Imperial Council of Agricultural 
Research. A Standing Committee on Rice consisting of forty-five members was 
constituted during the year on the lines recommended by the Crop Planning 
Conference, 1934. 

BENGAL contributed 25.8 per cent, in area and 28.8 per cent, in production 
of tho total Indian crop. The reported area^for the year, 21,092,000 acres, was 
pearly the same as in the previous year, but the production, 7,208,000 tons, had 
gone down by nearly twelve per cent. Plant-breeding work on rice is carried 
on at various stations and special attention is paid to the propagation of varieties 
and strains recommended by the Department. The number of seed-farms 
increased from 334 to 369, during the year, the area increasing from 3,000 acres 
to 3,025 acres. At the headquarters of the Economic Botanist, 2,075 types of 
highland aus (autumn paddy), transplanted union (winter paddy) and other 
rices' were under observation. The most promising of these are usually picked 
out by preliminary observations for detailed yield tests. During the year thirty* 
four selected varieties were under yield trials. A number of hybrid progenies 
were compared against the parents for hybrid vigour. A .large number of 
generations of crosses were under study. Histological studies on the distribution 
of mechanical tissue in the straw, were continued on materials from rices with 
lodging an<f erect habits and of their crosses. Results reported previously— 



184 , AGRICtJLTCft AL JOURNAL OF BRITISH GUIANA. [iX, 3. 

that copper sulphate treatment preserves the viability of seed during storage— 
are found to hold good only when the treated seed is stored in air-tight recepta- 
cles, Analyses of paddy and rice samples and oooking tests were carried out in 
connection with the co-ordinated scheme of marketing survey in rice initiated by 
the Imperial Council of Agricultural Research, Due to bad season and persistent 
drought several of the yield tests had to be abandoned. At the Bankura station 
several cultural and manurial trials were continued. In a complex experiment 
dealing with broadcasting, dibbling and transplanting with two ages of seedling, 
both dibbled and broadcast sowing gave a significantly higher yield than 
transplanting and between the two sowings, dibbling was better than broad- 
casting. The pot experiment with regard to the bost time of applying Nicifos 
showed that its application at a much later period than transplanting time is 
beneficial. Increased doses of Nicifos, were, as in the previous year, more 
effective on yield tillering than smaller doses. 

The province of BIHAR and ORISSA contributed 16.5 per cent, in area and 
14.8 per cent, in production of the total crop in India. Scientific work is carried 
on in the central station. The substations deal with simple selection in local 
varieties and in addition arrange for the trial of strains evolved at the central 
Station. Nearly 5,000 samples have been collected from different parts of the 
province aqd are being grown and examined with a view to eliminating dupli- 
cates and recording morphological characters. Selection work on types suitable 
for flooded conditions was also duplicated by subjecting the selections to flood 
conditions artificially and eliminating tile unsuitable types. The selection work 
in certain rices has resulted in a few improved strains which show promise of 
being better both in quality and yield than some of the present standard varieties. 
Over fifty rice varieties imported from outside the province were under observa- 
tion for determining their suitability to the Bihar conditions. A study of the 
root-systems of rice under different conditions of soil has shown the compara- 
tively better developed root-system in awcm as compared with (tun rices, and 
that the root-system is best developed in clayey soils, the mixture of sand in it 
inhibiting such development. The investigation on the factors governing 
44 Qu&lity of fineness ” in rice has shown that the weight of grain per unit length, 

iZ£h\?tT~ZnZ ia a much more reliable index than ordinary SIu ratioa - 
Several cultural experiments were continued. Trials on spacing and number of 
seedlings per hole in transplanted lice showed that it is more economical to 
transplant 9" apart with only two or three seedlings to the hole. Dibbling of 
seed was also found to be superior to broadcasting. The practice of dewatering 
the field for about a fortnight at a certain stage of the crop again failed to show 
any advantage over the normal irrigation practice. In the manurial trials, 
Ammophos and ammonium sulphate were both equally good as fertilisers and 
definitely better than sodium nitrate for South Bihar conditions, and superphos- 
phate was not of any value. Manuring of seed-bed did not show any beneficial 
e||ect on the subsequent growth and yield of the crop, and it appears that the 
best time of applying artificial manures to rice is about two weeks after trans- 
planting. 



NOTE. 


185 


On the physiological side, studies of the mineral and water requirements of 
the rice plant have been in progress. Ammonium salts appeared to be much 
more beneficial than nitrate salts. Ho water-requirements of the crop, there 
appeared to be a good deal of variation within each group of early, medium and 
late varieties. There is also a well-marked period of high water-requirement 
which starts about two to three weeks before flowering and continues right up 
to the flowering time after which it begins to decline gradually. Studies on 
salt-tolerance indicated the possibility of gradually educating varieties to tolerate 
salinity. Desiccating agents like calcium chloride or sulphuric acid were found 
to help the seed in retaining its viability for long periods, up to twenty-six 
months. A study of the F a generation of some crosses indicated great complex- 
ity in the inheritance of characters, both morphological and agricultural, and the 
work is being continued. 

BURMA claims on an average of the last three years 15.5 per cent, of the 
total area and 17.5 per cent, of the total production of India. The area and 
production during the year were 12,494,000 acres and 5,018,000 tons respectively. 
Unlike other major provinces, the production during the year was slightly above 
normal and about ten per cent, more than in the previous year. Although 
Burma is responsible for eighty-six per cent, of the total export of rice from 
India, the quantity exported during the year declined to 2,905,000 tons from 
3,599,000 tons in 1934-35. Since the rice industry in the province is dependent 
on her retaining her foreign market, attempts have been mainly devoted to the 
production of rices to compete with the high-grade American and Spanish rices 
in the United Kingdom and Canada. In addition to two improved Emata rices, 
two Ngasein types have emerged successfully from tests conducted at eleven cen- 
tres. These rices have been approved as suitable for both Western and Eastern 
markets and seed is now being grown for commercial milling and trial shipment. 
15,408,717 lbs. of improved seed was distributed during the year. The breeding 
work at the Central Station consisted of the study of 180 hybrid cultures of 
crosses betweeu local strains and local strains, and between local strains and 
exotic varieties to evolve high-yielding types with big, bold and translucent 
grain suitable for the export market. A large number of exotic .varieties was 
also studied but most of these did not prove suitable for Burma conditions except 
two from Siam. Under genotical studies, the inheritance of sterility proved 
complicated and no connection was established between sterility and pollen 
abortion. The inheritance of grain-size was of the usual multiple-factor type, 
and grain shattering was found to be dominant over non-shattering. Under 
manorial trials the experiment with a mixture of ammonium sulphate and sodium 
nitrate has definitely proved that ammoniacal nitrogen is to be preferred for 
rice. 


Investigations on the photoperiodism in rice conducted at Mandalay by the 
Economic Botanist have shown that the influence of the length of day profound* 
ly affects the time of flowering. By artificially shortening the day a rice variety 



186 * AGBicm/rmuL journo of British gviana. [IX, 3, 

can be induoed to flower in forty days from sowing which would normally 
require 135 days from sowing. There was, however, much sterility when 
flowering occurred during the hot day season (April). 

* 

MADRAS. — This province contributed about 13.5 per cent, of the area and 
to about 18.1 per cent, of the production of the total Indian crop. The reported 
area for the year was 10,478,000 acres and the production 4,880,000 tons. 
Nearly forty improved strains have been evolved suited to the varied conditions 
of rice-growing obtaining in the province and the area under them is rapidly in- 
creasing. Progress in the spread of strains was marked. Amount of seed sold to 
cultivators was 2,479 tons. Seed-farms under departmental supervision and 
through agricultural co-operative societies were arranged. Total area under 
different improved strains of rice including natural spread was estimated to be 
1,063,299 acres. Most of the fundamental work on rice is carried on at Coim- 
batore but the district sub-stations deal mainly with simple selection work 
in looal varieties and also conduct agronomic experiments suited to the 
local eonditions. Six strains from two stations are being released for general 
distribution to cultivators. Two strains from Coimbatore are of hybrid origin 
combining valuable economic characters. Under cultural experiments work 
at Coimbatore has shown that dibbling the seed in lines in puddle is just as good 
as transplanting. Manurial trials gave tbo following results : Phosphatic 
manures, in whatever form, had no response. At one station green manures 
were better than mineral fertilizers applied to give the same amount of nitrogen. 
At another station applications of nitrogenous fertilisers over a dressing of green 
leaves gave definite increases in yield and the increase is progressive with high- 
er doses of leaf application from two to ten thousand lbs. per acre and there is 
a definite residual effect with the heavier doses. Irrigation experiments at 
Coimbatore and Maruteru showed that in the former place a rice crop (August 
to January) consumes seventy-eight acre-inches with a duty of about fifty and 
that in the latter, the crop (June tc November) consumes fifty-four inches with 
a duty of about seventy. Under fundamental studies carried on in 
Coimbatore, the inheritance and linkage relationship of some of the morpholog- 
ical characters have been worked out. The cytogenetic study of a large num- 
ber of mutations isolated from the X-rayed material and polyploids was in 
progress and is expected to be of considerable help in determining linkage 
groups and the basic number of chromosomes in rice. Histological studies 
showed that the coarse and coloured rices have thicker bran layere than the 
fine and white rices. In connection with the marketing survey, a simple 
laboratory method for cooking test was designed. Two hundred and seventy- 
five samples of paddy and rice were analysed and cooking values determined 
for forty samples of rice. 

THE UNITED PROVINCES contribute 7.8 per cent, in area and 6.7 per cent. 
i% production of the total crop in India. The area and the production were 
6,643,000 acres and 1,983,000 tons respectively. The total quanity of seed 
distributed during the year was 993,594 lbs. The research work is carried op 



NOTH. 


187 


at Nagina. There were fifty-three varieties comprising indigenous and exotic 
ones grown as single plant cnltnres. Over a thousand cultures from hybrids 
were under study. The several manorial and cultural trials were repeated 
during the year. The one important observation made in the several manurial 
trials was that there was no difference among the treatments and none of them 
did better than the control. Interploughing of the broadcast crop one month 
after sowing failed to give any effect. An experiment with different quantities 
of water, forty, sixty and eighty aore-inches showed no differences among them, 
indicating that forty inches was quite enough. Studies on germination and 
viability of rice seed showed that in early and medium ripening types the 
panicles might be harvested twenty days after their emergence without affect- 
ing the viability of the seed adversely. Hulling trials showed a correlation 
between fineness of grain and breaking percentage. The fine-grained types 
gave a higher percentage of broken grains than bold fine, medium fine and short 
and round types. Re breakage during milling, crude parboiling of paddy was 
superior to “dry” hulling. Though storage improved the hulling properties, the 
hulling quality did not differ betwoen transplanted and broadcast rice. 

THE CENTRAL PROVINCES AND BERAR contribute 6.9 per cent, in 
area and 5.8 per cent, of India’s total production on an average of three years. The 
area and production were 5,665,000 acres and 1,484,000 tons respectively. The total 
quantity of rice distributed as seed during 1936 was 12,966,250 lbs. Research 
work is carried on at Raipur and special emphasis is being laid on biochemical 
problems. Results of chemical analysis have shown that a high percentage of total 
phosphoric acid in the soil does not necessarily lead to a high yield in rice and 
that there appears to be an inverse relationship between the lime-content of the 
soils of a particular tract and the yields of rice obtained. Determinations of 
soil-acidity have shown that in the case of most of the soils examined, the 
acidity increases with depth and high yields of fine varieties of rice can 
be obtained only from neutral or slightly acidic soils. Most of the soils 
examined showed a lack of humus, its percentage being highest within 
the top six inches. The humus content did not show any relationship 
to the carbon-nitrogen ratio, which varied widely with different soil groups 
and was lower at a depth of six' to twelve inches than in the top six 
inches of the soil. The existing varieties of rice grouped according to their 
times of ripening and quality were tested for yield and 168 out of 803 have 
been retained for further trial. The hybridisation work in progress has got a 
double object in view, namely, securing heavy-yielding types, and types with 
deeply pigmented morphological parts as leaf-sheath, auricle, etc., to 
distinguish them easily from wild rice. Experiments with nitrogenous and 
phosphatic manures either singly or in combination showed that there was no 
response for nitrogen even up to forty pounds per acre and the response to 
phosphoric acid did not vary for applications of twenty to forty pounds per acre. 
Comparison of Nicifos with ammonium sulphate showed that the former had a 
residual effect while the latter had not. Varying doses of Nicifos from fifty 
to three hundred pounds per acre all gave significantly higher yields than the 



1§5 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 3. 

no-mannre plot and the higher doses left a greater residnal effect than the 
smaller doses. The caltnral experiment with broadoasted and subsequently 
oross-plonghed, drilling, etc., showed that on sandy loam land, in all varieties 
tried, transplanting was better than broadcast-sowing and drilling. 

A -ISAM contributed to the total rice area and rice production in India 
6.1 an i 5.4 per cent, respectively on a three years’ average. The acreage and 
production were 5,292,000 acres and 1,610,000 tons respectively. The research 
work is carried on at Karimganj and Titabar. A certain number of strains, 
selections and cross progenies suited to conditions have already been evolved 
and distributed, such work forming one of the important activities of the 
department. Work with varietal, cultural and manurial trials besides breeding 
and selection were carried out. Under the scheme of analysing market 
samples of paddies and rices to fix grade standards, 134 samples were examined. 
Cooking tests were also conducted with twenty-two samples of rice. Problems 
relating to deep water rices are peculiar and entail special equipment to study 
them properly. Cultural experiments with time of sowing and seed-rate and 
complex experiments involving time of planting, spacing, age and number of 
seedlings per hole in certain rices have been laid down and preliminary 
results obtained. 

A 

BOMBAY contributes on an average of the last three years 2.4 per cent, in 
area (1,832,000 acres in 1935-36) and 3.1 per cent, in production (740,000 tons 
in 1935-36) to the total rice crop in India. Bombay imports considerable 
quantities of rice from Burma and other proviuces and re-exports portions of 
it to Africa, Persian Gulf, etc. During 1936, 30,000 lb. of seed was distributed 
to registered seed-growers. The area under the improved strains is estimated 
to be 13,524 acres. Breeding work is carried on. 

SIND contributed about 1.5 per cent, of India’s production out of a little 
over a million acres. 497,822 lb. of seed was made available to cultivators. 
Breeding work is carried on which has resulted in three improved strains. The 
improved hybrid strain obtained by crossing Kangni 27 with Kolamba 184 and 
which has been named 4 Silver Jubilee ’ rice was tried at several places on a 
large scale and has given satisfactory results, the yield per acre going up to 
3,400 lb. A large number of exotic varieties has been tried but most of them 
are not promising. Experiments with duty of water showed that a normal 
crop with fairly good yields can be raised in a normal season with thirty duty, 
the crop consuming about forty-five to fifty-five acre-inches. 

Rice is a minor crop in the PUNJAB and oocupies less than a million acres. 
Breeding work is carried on and a total supply of 355,962 lbs. of seed of 
improved varieties was distributed. A large number of local varieties (sixty- 
four) has been tested at the Btation and variety 246 Suffaida continues to be 
oufttanding. Under cultural trials transplanting is found to be better than 
broadcasting and seedlings of ages above si* weeks were better than younger 
Seedlings below five weeks, 



NOTE. 


189 


The HTDERABAD STATE contain* over a million acre* under rice in 
1935*36, bat produces only about 336,000 tons of rice. Selection work has 
given two early types. Other more promising types are under test. The area 
under improved strains during the year is 1,765 acres. 

The area under rice in MYSORE during the year was 741,000 acres and 
the estimated production 222,000 tons. Breeding work is carried on. Some of 
the new Mysore selections are very promising and district trials have created a 
demand for them by the cultivators. During the year 65,000 lb. of padi seed 
was made available to cultivators and the area under improved strains in the 
State is estimated to be 53,000 acres. 

The area under rice in the TRAVANCORE STATE is small and nearly fifty 
per cent, of the requirements has to be met by imports. Side by side attempts 
are in progress by the Agricultural Department to improve the yields in existing 
areas by the spread of improved strains and by advocating better manuring 
practices. During the year 6,88!) lb. of seed was sold. Certain manurial trials 
in progress have shown that addition of bone-meal, fish guano or laurel cake 
definitely increases the acre-yields. 

COCHIN. — Rice is an important crop and though no regular breeding work 
is done, simple selection has been attempted and one of the strains evolved is 
becoming popular. Manurial trials in rice have shown the importance of 
organic manures. 

Breeding work on a small scale is being carried out atKARNAL station. 
A preliminary experiment with four types of rice showed that transplanting 
seedlings with regular spacings was better than the local practice in which no 
regular space is maintained. 

F.B. 



NEWS. 

The Director at Agriculture visited Berbiee tram September 14 to 17. 

The Deputy Director of Agriculture visited Berbiee from August 22 to 26 
and Essequibo from August 29 to September 3. 

The Government Veterinary Surgeon visited Berbiee on several occasions in 
an effort to control an outbreak of anthrax in that area. 

Members of the Essequibo Central Rice Mill Committee including the 
Director of Agriculture and Mr. H. D. Huggins visited Essequibo on July 8 in 
order to make an inspection of the mills and to interview those connected with 
the Essequibo rice industry. 


Mr. James D. Gillespie, B.Sc., Agricultural Superintendent in this Depart- 
ment. left the Colony on August 30, on six weeks' vacation leave from date of 
arrival in the United Kingdom, prior to taking up his new post as Agricultural 
Officer, Sierra Leone. He takes the best wishes of his colleagues with him in 
his new sphere of activity. 


With effect from September 12, 1938, inclusive, Miss N. Green, Class III 
Clerk of this Department, has been seconded to the' General Register Office and 
Miss S. Lord, Probationer of that office, has now joined the staff of the 

Department of Agriculture. 

% 

Mr. H. Balkaran Singh, of the Sugar Experiment Station Laboratory, has 
passed the Final Examination in Sugar Technology of The City and Guilds of 
London Institute. Mr. Singh is to be congratulated on his success. 

Mr. Hubert Parker, Manager of Government Rice Mills, Federated Malay 
States, who has been detailed to investigate the possibility of the erection of a 
Central Rice Mill in Essequibo, and generally to go into rice milling problems in 
the Colony, arrived in British Guiana on September 19. Before leaving for 
the districts, Mr. Parker is spending the first few days of his visit in George- 
town studying matters connected with the industry. 

Among the visitors to bihe Department was Mr. Herbert G. Ford, Sales 
Representative of the U.S. Phosphorio Produots Corporation, Broadway, New 
York. 

A meeting of the Advisory Board of Agriculture was held on Wednesday, 
August 10. 

Efforts are being made to reawaken local interest in poultry and the Poultry 
Association has been resuscitated. Meetings were held at the Head Office, 
Department of Agriculture, on August 12 and 19 and September 5. Rules were 
drafted and adopted and a President and other officers elected. 

At a Village Chairmen’s Conference held on Tuesday, August 16, at La 
Gringe, West Bank, Demerara, His Excellency the Governor attended and gave 
an address. The Director of Agriculture was also present arid made a short 
reference to the possibilities of a poultry industry in village areas. 



PLANT AND SEED IMPORTATION. 

Introductions by the Department of Agriculture for the period 
J une — September, 1938. 


Kami 

Quahtity. 

Whence Supplied 

Economic, 



Mango, 7 varieties 

4 seeds each 

Puerto Bieo Agrl. Experiment 
Station. 

Cauliflower (Maincrop Benares) 

2 oz. 

Sutton & Sons (Calcutta). 

Dioscorea (data 

tubers 

Agrl, Dept., Dominioa, 

Padi, 6 varieties 

} oz. each 

Orissa, India. 

Padi, 5 varieties 

i oz. each 

Sflo Paulo, Brazil. 

Guava, 3 varieties 

1 oz. 

Kirkee, India. 

Peas, 14 varieties 

i oz. each 

Pnsa, India. 

8 rgo, 2 varieties 

i lb. each 

U.S. Dept, of Agric., Wash- 
ington, D.C. 

Bananas, (Hawaiiau Cooking) 4 
varieties 

Buckers 

Canal Zone Expt, Gardens. 

Ornamental. 



Early Flowering Sweet Pea • 

2 pkts. 

Sutton & Sons (Calcutta). 

Nelunbium luteum 

3 os. 

Dept, of Agriculture, Jamaica. 

Frangipanni, 3 varieties 

cuttings 

Dept of Agriculture, Barbados. 

Alttonia sp. 

1 pkt, 

Dept, of Agriculture, Bermu- 
da, 

Ptrittropht tpteiota 

< 

do. 

’ 

Dept, of Agriculture, Bermu- 
da. 







METEOROLOGICAL DATA— AERIL TO -JUNE, 1938. 


Recording Stations k 
Months. 


Botanic Gardens. 


April 

May 




NUMBER Of DAYS Of RAIN 


5 " li 

S s g-S" 55 
5 «g «8 


Totals 


19 8 


Air Temperature 
and Humidity. 




44 7 844 76-3 80-3 82-0 
44 2 84 9 76-2 S0 5j 84-8 
3-92 84-5 75-3 79-9 84.3 


72 12.21 


Means 


84.fi 75.9 80-2 83-7 


Berbice Gardens. 


8-84 (5 9 3 


4 2 22' 
1 1 26 


864 75.1 80. 7 1 82-9 
I 87.7 75.5 81-6 82-9 
i 87-2 75-1 81 4 1 80.9 


Totals 


39 60 20 


Means 


87.1 75-2 814 82-2 


Onderneeming. 


April 

May 


Totals 


11.21 1 
14-80 3 


38-59 6 



84-9 74.5 79-7 90.9 
854 744 79.6 92.4 
81-6 72-7 78-6 934 


Means 


84-9 73-8 79-3 924 


Hosororo, 

North West District I 


Lpril 
lay 
une 4 


... 10-91 7 

... 12-31 4 

.. 13-80 3 


84-8 70-5 77-6 864 
85.5 71 .6 78-5 88-6 
85.7 714 784 87-5 


Totals 


37-02 14 


CURRENT Hfc!<3ES PRODfCE 

Front The Commercial Review Journal, of the Georgetown Chamber 
of Commerce , Vol. XXI, No, 8, Wednesday 31st August, 1938. 

SUGAR, 


Per 1QO lb; net 3 lb. per Bag allowed for tare 

Dark Crystals for Local Consumiption 13.30 

Tellow Crystals do. ' do. .'... $4.00 

White Crystals $4.75 

.Molasses Sugar none offering. 

Above Prices include Excise Tax of 90c. 


RUM. 

Imperial Gallon. Cask included. 

Coloured, in Puncheons — 40 to 42T O.P:..(for export). ..60c.; Hhds.52c., Barrels 77c* 


White, in Hogsheads— 40 to 45 O.P...(for local consumption) 45 to 55c. 

MOLASSES. 

Per Imperial Gallon. Naked. 

Yellow (firsts) 10c. 

Yellow .(seconds) .....5$c. 


RICE. 

Rice per Bag of 180 lb. gross. Brown Super $5.00 scarcity ; Extra No. 1, 

$4.25— $4.50 j White, None available. Lower Grades $3.35 — $3.65 as to quality 
Padi per Bag of 143 lb. gross, $1.20 — $1.50 as to quality. 


GENERAL. 


Gold, Raw, average per oz. $26 to $27. 

Diamonds, — pro rata as to quality ...average per carat $10 to $11. 

Timber, Greenheart, (Lower grade measurements). ..40c. to 60c. per c. ft. ; 

for export 72c. to $1.00 perc. ft. 

do. Railroad Sleepers — (Mora) $1 .68 each. 

Greenheart Lumber $70 to $80 per 1,000 feet. 

Crabwood Lumber $60 to $75 per 1,000 feet. 

Shingles, Wallaba, 4 x 20 and 5 x 22 inches $4.50 to $6.00 per M. 

Charcoal, Capped for shipment., -.. 72c. to 85c. per bag. 

Firewood $2.50 per ton. 

Cooonuts... Selects, $9.00, culls $6.00 per M... Copra $2.50 per 100 lbs. prime Copra. 

Balata ..Venezuelan, none. Local Sheet... 36c. to 38c. per lb. 

Cocoa 19c. to 19ic. „ „ 

Coffee 6c. te 6ic. „ „ 


N.B. — Duty Payable on value at time of Importation and rate of exchange on day of 
arrival. 



THE CERTAINTY 
OF DAWN. 



In quiet confidence-* 
and in the adherence 
to sound business prin- 
ciples— lies the way to 
true success. The Royal 
Bank offers to legiti- 
mate enterprise the 
security and prestige 
which sixty-six years of 
experience have built 
up. • • • * 

Tfl E 

ROYAL BANK 

OF CANADA 


llllllllllllBUIfIlillllllltli|lllliaillllIltlUlllljllflltllItlIfltllll 1 llltlttltl«naillillUllll!llltlMlll«Ill!tllllUlillt!Slt 8 III 218 lt 8 !||llBliailll>lUllllUlltlUI)IIIIIUai!IUatlllli 


ELECTRIC MOTORS | 

ARB IN A CLASS BY THEMSELVES FOR DRIVING— 

DRAINAGE PUMPS 

and other Machinery connected with Agriculture. 

■ - ■ ♦ — 

The Benertri Electric Ctipaiy, Ltd. 

Headqmsrtere for Electrical Supplier. 






VoL IX, No. 4 * 


December, 1938. 


The 

Agricultural Journal 

Of 

British Guiana 



PUBLISHED BY 

THE DEPARTMENT OF AGRICULTURE, 

GEORGETOWN, B1UTI8H GUIANA 


Price 


$d, 




Mttftfft&itf of iseittcotTME, 


AWHNISTRATfON 


Director of Agriculture ... 

Deputy Director 

... 

Clerical Staff. 

Prof. The Hoau J. Sydney Dash, 
B.Sc. (Agnc.) 

(vacant) 

E. M. Peterkin (acting) 

Senior Clerk 

••• 

J. F. Irving, M.C. 

Registrar of Banks 

... « 

W. G. Delph (on leave) 

A. A* Thorne (acting) 

Class III Clerks 

.. * 

0. A. Lsshley (acting) 

Miss D. M. Terrill 

Probationers 

.. . 

/ Miss M. Cbeong 

I P. 0. Jackson 
j 8iA, Adams 
j Miss S. Lord 
^ Miss R. Delph 

Librarian ... ... 


Miss V. Chan-Choong 


RESEARCH BRANCH. 

Botany and Plant Pathology 

Botanist — Plant Pathologist and Superintend- 
ent, Botanic Gardens : 

E. B. Martyn, B.A., A.I.C.T.A. 

Technical Assistant : 

N. Persaud 

Chemistry 

Chemist : 

D. W. Duthie, M.A , B.Sc., Ph.D., F.I.C. 
Assistant Chemist : 

C. L. C. Bourne 

Entomology 

Entomologist ; 

L. D. Cleare, F.R.Ent.S. 

Technical Assistant : 

C» Williams 

Rich 

Assistant Plant Breeder : 

P. A. ChanChoong, B.Sc., A.I.C.T.A. 

Sugar 

(In co-operation with the Sugar Produoers) 
Sugar Agronomist and Plant Breeder : 

c. H. B. WillianifeJfcA*, A.I.C.T.A., Dip, 
Agr. (on leave) 

Laboratory Assistants : 

H. B. Singh* 

A, V, Wan*Ping, Dip. Agr. 
matisHcal Clerk t 
J* B. Bourne 


LIVESTOCK BRANCH 

Veterinary Surgeon: 

£* O.B.E., M.R.C/V.S. (on leave) 

H A Fraser, B.V. Sc (acting) 

FIELD BRANCH 

Agricultural Superintendents : 

Berbice— (Vacant) 

Demerara, Bast — E. M. Peterkin 
Demerara, East Bank— H. D Huggins, 
M.Sc., Dip. Agr. 

Demerara. West — E. G. Benson, B.Sc,, 
A.I.C.T.A., Dip. Agr. 
Essequibo— A. A. Abraham 
Assistant Agricultural Superintendent: 

Betbioe — E. M. Morgan 
Agricultural Instructors ; 

Botanic Gardens— H. A. Cole 

(C. 0. Dowding, F.L.S., 
Demerara, East— ■< F.R.HLS. 

vG. L. Leitch (acting) 
Demerara, East Bank — I. Dewar (acting) 
Essequibo— A. W. Sears 
North West District— L. B. McKinnon 
Berbice— O. F. Jt Clmraman, Dip. Agr. 
Agricultural Assistants;. 

Demerara, East— J: Ihdrobehacry 
Berbice— H. B. France • 


Sugar 

Field Manager (Central Static*) 
C, Cameron 
Field Assistants i 
L. A. Forte 

B. A. McArthur % 



MtetEOiiOtOGiCAL BfeA^Ctt 

technical Assistant : 

D. D. Blackman 

Meteorological Assistant : 

J. E. Isaacs 


ftJCE GRAttfoG 'hRANCh 

Grading Inspector: 

H. E. H. Gadd (on leave) 

H. D. Hoggins (acting) 

Technical Assistants ; 

W. A, Boveii (acting) 

R. R. Ross 


ADVISORY BOARD OF AGRICULTURE 

Director of Agriculture, Chairman, ex officio. 

Deputy Director of Agriculture, Vice-Chairman, ex officio. 

Hon. 1 Peer Bacchus ... ... ... \ 

Hon. R. E. Brassington ... ... ... I 

Hon. J W. Jackson ... ... ... [ 

Hon. F. J. Seaford, o.b.e ... ... ... > Members 

Mr. S. Andries ... ... ... ... I 

„ R. B. Hunter ... ... ... I 

,. W. H. Richards ... ... ... / 

SUGAR EXPERIMENT STATIONS COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 
Hon. M. B (t. Austin, o.b.e. 

Mr. G. M, Eccles 
„ J. C. Gibson 
„ A. Murison 
„ R. E. Rhodes 
„ J. Bee 


Georgetown 
Pln^filairmont 
Pin. Port Mourant 
Pin. Uitvlugt 
Pin. Diamond 
Pin. Albion 


N Representinj 
the Sugar 
Industry 
which main* 
tains the 
/ Stations 


CO-OPERATIVE CREDIT BANKS’ BOARD. 

Director of Agriculture, Chairman, ex-officto. 

Hon. J. W. Jackson 
Rev. A. E. Dyett ... 

Mr. C. Farnum ... 

„ J. L. Wills ... 




Members 


DISTRICT AGRICULTURAL COMMITTEES 

EAST DEMERARA 


Director of Agriculture, Chairman 
District Commissioner 


Deputy Director of Agriculture 
Hon. J. I. de Aguiar 

... 


Hon. E. M. Walcott 


.. 

Mr. S. Andries ... 

» • 

... > Members 

„ M. Ghaui 

... 

... [ 

„ W. H. Richards 


... 

„ J.E. Wills ... 

... 

/ 


WEST DEMERARA 

Director of Agriculture, Chairman 
District Commissioner 
Deputy Director of Agriculture 
Hon. J. W. Jackson 
Dr. the Hon. J. B. Singh ... 

Mr. R. P. Carryl 

,% J. C. DaSilva ... ... ... ► 

„ R. B. Hunter 
„ A. Murison ... 

„ W, Ramdeholl 
„ A. Baym&n ... 


Members 



contents. 

(Vol. IX, NO. 4.) 


EDITORIAL — 

ORIGINAL ARTICLES. 

Malaria in British Guiana, . . 

Part III. ... ... O . GiffhW , M.D , (//,), M.R.C.P. ( Bond .), 

D.TJd.&H.(Eng.) ... 


The Georgetown Botanic 

Garden ... ... E. B. Uartyn , B.A., -4.J.G.7L4. 

A Water Rat (Hoplochilus 
sciureus berbicenais Mor- 
rison- Scott) Damaging 
Sugar-Cane in British 

Guiana ... ... L. D. Cleave , F.R<Ent.S. 


197 

207 


217 


A Short History of the 
Rupununi Savannahs with 
Special Reference to the 

Livestock Industry ..* EL. E. Turner ... ... 230 

Damage Caused to Rum 
Puncheons by Boring 

Beetles ... ... L. D . Cleare , F.U.Enf.S. ... 237 


A Summary of Agricultural 
Legislation in British 

Guiana ... ... ... ... ... ... 240 

REVIEWS. 

Cacao and Witch Broom 
Disease {Marasmius perni- 
ctosus ) of South America 


by F. J. Pound ... ... ... ... ... 263 

The Principles of Cane 
Sugar Manufacture by J. 

G. Davies ... ... ... ... ... ... 264 

NEWS ... ... ... ... - ... 265 

LEGISLATION ... ... ... ... ... 267 

PLANT AND SEED IMPORTATION ... ... ... 268 

METEOROLOGICAL DATA ... ... ... ... 269 

CURRENT PRICES OF COLONIAL PRODUCE ... ... 270 

« ILLUSTRATIONS 


Facing Page 

Plate I. — Figs. 1 & 2 — Typical breeding sites of A. davlitigi 

in the interior. ... ... * ... 198 

PLVTE II. — Fig. 3 — Typical breeding site of A. darluigi in 

# the interior. Rain water swamps in the 

mid-Demerara. ... ... ... 199 


„ — Fig. 4 — Abandoned factory sites, with bush covered 
foundation pits and obsolete canakj, form 
ideal breeding sites for A. ddrlingi « Ml 199 



Contents— (Continued ) . 


Facing Page 

late III. — Fig. 5 — Plan of irrigation canals, drains and' 

drainage trenches in a group of four sugar 

cane fields. ... ... ... 200 

LATE IY. — Figs. 6 & 7— Typical breeding sites of A. darhngi 

on the coast. ... ... ... 201 

’late V. — Fig. 8— Flooded fields lying fallow, when covered 

with floating and vertical vegetation and 
favourably exposed, may be productive 
sources of A . darlingi . ... ... 202 

„ „ — Fig. 9 — Rice fields situated beyond the salt coastal 

front lands, and sheltered by trees and 
scrub are favourite breeding sites of 
A . darhngi. ... ... ... 202 

Plate VI. — Fig. 10 — Open, windswept rice fields in the salt 

coast front lands are favourite breeding 
* sites of A . tarsimaculains , but only very 

exceptionally harbour A . darhngi . ... 203 

Plate VII. — Fig. 1 — The Entrance Qates and Lodge today ... 208 

Plate VIII.— Fig. 2— The Main Avefnue and “Flower Garden” ... 209 

Plate IX. — Fig. 3— The “ Oronoque Avenue” now the Cen- 
tral Avenue through the Park Lands. ... 210 

Plate X.— Fig. 4 — The Band Stand and “Flower Garden.” ... 211 

Plate XI, — Fig. 5 — The Iron Bridge over No. 2 Lake ... ... 212 

Plate XII. — Fig. 6 — Jenman’s House and Herbarium, now the 

residence of the Director of Agriculture. ... 213 

Plate XIII. — Fig. 7 — Lotus Lilies in a Lake in the Park Lands. ... 214 

Plate XIV. — Fig. 1 — Nest of Uoplochilus sciureus bcrbicensis 

M-S, made of cane leaves ... ... 218 

„ „ —Fig. 2 — Estate dam showing Razor Grass which 

served as cover for rats. ... ... 218 

Plate XV.— Fig, 3 — Damage to cane stalks by Hoplochtlus 

Bciureus berbicemis M-S. ... ... 219 

„ — Fig. 4 — Damage to tops of cane shoots by Hoplo - 

chilus sciurem berbiccnsta M-S. ... ... 219 

IPlatb XVI, — Fig. 5 — Ratcatchers with dogs working over sav- 
annah recently empowered and ploughed ... 226 

,, — Fig. 6 — Ratcatchers with their “hunting dogs” 

* working in taller canes ... ... ... 226 

Plate XVII. — Fig. 1 — The effect oh Pasture of overstocking ... 222 

„ * —Fig. 2— Cir«rt?red Zebu Hereford Heifir. ... ... 222 

Plate XVI !l!— Fig. 3— A Herd crosslag tho Sittronuni River ... 223 

—Fig, 4— Driving a Mixed $Ierd ... ... ... 223 



The 

Agridtvsl Journal of British Guiana. 

Member, 1938* 

EDITORIAL. 

ROYAL COMMISSIONS-PAST AND PRESENT. 

When the Royal Commission arrive here early next year it will be just over 
42 years since the last Royal Commission was in the Colony, and comparison of 
the state of affairs then and now gives food for thought. Since the last Com- 
mission the wheel has turned a full cycle, tor from the state of depression which 
brought about the arrival of the first Commission, the Sugar Industry, ever the 
mainspring of the colonies, has risen to prosperity during the boom years of the 
war, and dropped back again to necessitate the Sugar Commission of 1929. Des- 
pite the advances made by the industry both in field and factory, the last nine 
years have been difficult ones and, economically, the planters today are again faced 
with a position similar to that obtaining in 1896, but it is to be hoped that the 
wheel has passed dead contre and that its further movement will be toward 
better times. 

The Commission appointed in 1896 consisted of General Sir Henry Norman 
as chairman together with Sir Edward Grey, Sir David Barbour and Mr. (after- 
wards Sir) Daniel Morris as Agricultural Adviser. Its Secretary, Mr. Olivier, 
was destined to re-cover the ground when, as Lord Olivier, he and Mr. Semple 
constituted the Sugar Commission of 1929. The ’96 Commission came into 
being as the result of intense depression b: ought about in the sugar industry by 
the competition from Beet sugar produced in Europe under a system of bounties. 
An appeal for assistance from the Home Government had been made by the 
planters and all those whose fortunes were bound- up with the industry. British 
Guiana was one of the colonies most seriously endangered by the existing state 
of affairs, and it was to this Colony that the Commission came ficst on leaving 
England, passing on to the West Indian islands and ending in Jamaica, where 
the effects of the depression were less serious than elsewhere, owing to the in- 
creasing number of peasant proprietors, and the possibility of substituting other 
crops for sugar, notably coffee, and also bananas, which were already coming 
into prpmincnce. 

The present Commission has begun its enquiries from a different 
point in more ways than one. In the first place, its primary object 
is to investigate the conditions of labour in the colonies visited, in 
other words, this time the difficulties of the employee* rather than 
the employer^ formed the basis of its appointment which was made, 




196 


AGRICULTURAL JOUBSAL Of BRITISH GUIAHA* 


Ut, t 

not after an appeal from the colonies, but as the result of discussions In 
Parliament after the labour unrest in Jamaica had followed closely upon the 
serious disorders in Trinidad last summer. The Commission this time has visited 
Jamaica first and will end with the southern colonies, its scope also Including 
British Honduras, whioh was not visited before. 

'We may now consider more closely ttie two Commissions in their relation 
to British Guiana. When the Norman Commission came to the Colony they 
were largely concerned with the possibilities, if any, of finding a substitute for 
sugar, which then, as now, formed 70 per cent, of the Colony’s total exports. At 
that time, gold had recently come into prominence in British Guiana, and it was 
hoped that it would render considerable help towards swelling the Colony’s 
depleted revenue. Mr. Morris had painted for the members of the Commission a 
most glowing account of the agricultural possibilities of the interior, which they 
would not allow to be damped to too great an extent by the somewhat conflicting 
evidence of the Director of Science and Agriculture, Sir John Harrison. 

Crops, the cultivation of which it was suggested at the beginning of the 
century could well be extended, included coffee, fruit and rice. The viscissitndes 
which these have undergone in the ensuing years need not be recapitulated — 
suffice it to^ state that the only crop which has been able eventually to establish 
itself in a position of importance, though still very far behind sugar, is rice, 
which now constitutes approximately 8 per cent, of the Colony’s total exports. 
The answer however, to the query whether the Colony is dependent on a single 
export crop to a dangerous extent must still be in the affirmative. The position 
however, is slightly better than it was in 1896 when, if gold were excluded, sugar 
formed 94$ per cent, of the total exports, and if marketing problems can be 
solved and milling put upon a sounder basis, rice may be able to exert an ever 
growing influence on the Colony’s budget. 

But the present Commission is largely ooncerned with labour and conditions 
affecting the labourer ; it includes Sir Walter Citrine and two women members 
with considerable experience of social and health questions. All classes will be 
given a chance to disclose their grievances, and by the time the Commission 
reach Georgetown the information and experience that they have gained in the 
early part of their journeyings will enable them to see these in perspective and 
judge them on their merits. There have been no labour disturbances in this 
Colony comparable to the rioting and disorder which occured in Trinidad and 
Jamaica, but there have been a number of strikes throughout the past eight 
months and a continual undercurrent of unrest, which has hampered the routine 
of the sugar estates and disturbed the current of the lives of the great majority 
of labourers and peasantry, whether discontented or not. 

We welcome the arrival of the Commission and hope that when the basic 
problems have been discussed with its personnel, and we have been enabled to 
benefit by their deliberations, the Colony with its strangely heterogeneous 
population will unite to further the turn of the wheel towards prosperity. 



MALARIA IN BRITISH GUIANA. 

Paw III. BREEDING HABITS OF A. darlingi. NATURAL FACTORS 
WHICH LIMIT THE DISTRIBUTION OF THIS SPECIES AND OF 

MALARIA. 

BY 

G. GIGLIOLI, M.p. (It.), m.B.C.p. (Loud.), d.t.jc. & h. (Eng.) 

Medical Adviser to the Sugar Estates of British Guiana, 


We have established in the previous sections that A. darlingi is the sole 
malarial vector of practical importance out of the three local common Anopheles; 
we will now proceed to study the breeding habits of this species as such know 
ledge is essential for the carrying out of an intelligent control policy. 

Breeding Habits on A. darlingi in the Interior: 

We have seen that A darlingi is the main malarial vector throughout 
equatorial South America ; it is eminently an inhabitant of the vast inland forest 
districts of this region. 

Our observations, in this Colony, have been carried out on the mid and 
upper Demerara, mid-Essequebo and Potaro Rivers. These districts offer good 
examples of the various conditions which exist in the interior, as regards surface 
water regime. 

The Demerara River is subject to tidal variations for a distance of close on 
100 miles from its mouth, where the first rapids are found. The river banks are 
formed by low, alluvial mud fiats entirely covered by forest. The first sand 
dunes, which are also covered with dense vegetation, rise 25 miles from the sea 
and extend some 50 or 60 miles, when higher hills and rock formations make 
their appearance. The mud flats present a somewhat higher bank or dam 
bordering the river ; on this all the settlements are placed. 

The flats tend to get lower as one proceeds from the river bank towards the 
foot of the sand dunes, where extensive forest swamps are usually to be found. 
Some of these swamps are subject to regular tidal invasion from the river ; their 
waters are limpid, soft, dark brown in colour, and very acid (pH 4 to 5). They 
are very poor in algae and other vegetation ; the naked, black submerged trunks 
and limbs (TacobasJ have a characteristic charred appearance; planktonic life 
also appears to be remarkably scarce, 



198 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 4. 


Acid, peaty waters of this description form a very large proportion of all 
sarfaoe waters in the interior ; they appear to be unsuitable for the breeding of 
A. darlingi as we hare never found them harbouring larvae of this species. 

In some localities, white water springs exist at the foot of the sand hills ; 
in the absence of direct communication with the river or with brown water 
creeks, clear white water swamps tire formed ; such waters are only slightly acid, 
and sometimes neutral in reaction (pH 6 to 7). Vegetation of all kinds is here 
more abundant, and green algae are frequently noted, covering the submerged 
logs. These white water swamps are favourite breeding sites of A. darlingi ; 
being permanent they are particularly dangerous, and in their neighbourhood we 
have found this species ail the year around (Figs. 1 & 2). 

During the heavy rains, from May to July, extensive rain water swamps 
collect in low places not subject to tidal invasion; these too form suitable breed- 
ing sites for A. darlingi . Finding the larvae is a labourioqs task as their disper- 
sion is very great. When the dry weather sets in, most of these rain water 
collections disappear ; in others the characters of the water gradually change 
through prolonged contact with decaying vegetation, a'nd they become aoid and 

unproductive of Anopheles (Fig. 3). 

% 

In conclusion : 

The acid dark waters of the tidal rivers and of the black forest creeks 
and swamps, tidal or otherwise, are permanently unsuitable 
for the breeding of A. darlingi. 

Rain water collections and* swamps are suitable ; they give rise to only 
temporary or seasonal breeding. 

White water seepage swamps and creeks are dangerous and more or 
less permanent and productive sources of A. darlingi. 

Besides the physio-chemical characteristics of the waters, other factors 
influence the breeding of A. darlingi. 

Fairly large volumes of water are preferred; a fair combination of shade and 
direct sunlight appears to give optimum conditions ; a certain amount of cover in 
the form of vertical vegetation and floatage are required. 

The seasonal factor is also important ; breeding is active during the warm 
weather following the spring and early summer rains; it is scarcely affected by 
the autumn rains. These, in fact, actually appear to have an unfavourable bear- 
ing on the survival of the adult Anopheles from one season to the other; 
conversely, failure of the November-December rains is often a prelude to an 
unusual Anopheline and malaria prevalence in the following summer. 

Min-made breeding sites are of little moment along the tidal rivers. The 
Berbice, Pomeroon and Moruka rivers all present similar characters to those we 
have described on the Demerara. 



Plate I. 



Figs* 1 4k 2* — Typical breeding sites of A. darlwqi in the interior : white water seepage swamps on 
the mid-Demerara Biver. Though apparently completely covered by luxuriant 
vegetation, the water is exposed to a certain amount or direct sunlight. 




Plate II. 



Fig. 4. —Abandoned factory sites, with bush covered foundation pits and obsolete canals, form ideal 
breeding sites for A. darlmgi . 







malaria is British ggiaka. 


190 


The mid-Essequebo river is subject to regular, periodic floods; the poise of 
these floods is regulated by the rainfall over large tracts of land in the far 
interior* In these continental areas the distribution of the rainfall is much more 
characteristic and constant than on the coast : there is a single and well defined 
rainy season, from May to August. 

These Essequebo floods, therefore, as the inland rainfall which causes them, 
are regularly periodical, reaching their peak in the month of August. During 
the floods hundreds of square miles of forest are submerged over the 600 mile 
course of this great river. 

The waters of the Essequebo are of a very light brown colour, and their 
reaction is only slightly on the acid side. These physio-chemical features vary 
considerably along the course of the river according to the characteristics of the 
waters of the larger tributaries. The Potaro, for instance, brings to the Essequebo 
a large volume of dark brown acid water, and the two currents keep separate for 
some miles after their confluence. 

The mid-Essequebo valley is flooded during the local early summer rains. 
These local rains, conversely to what occurs on the tidal rivers, can have little or 
no importance as regards the breeding of Anopheles. We found at Rockstone and 
Butakari that A. darling i made its appearance during and immediately after the 
floods, when the falling river waters left behind extensive swamps presenting 
favourable conditions for the breeding of this species. Here again the finding 
of larvae is a difficult task owing to their wide dispersion. 

At Rockstone A. darhng i is particularly abundant, as the small clearing, 
surrounded by forest, offers those conditions of shelter, shade and sunshine which 
we have already described. 

This peculiar complex of conditions which prevail on the mid-Essequebo 
causes the seasonal incidence of Anopheles and of Malaria to be remarkably 
regular. 

These are the reasons for which the epidemiology of Malaria differs pro- 
foundly from one district of the interior to another : in 1926, for instance 
Malaria prevailed in severe epidemic form throughout the Demerara and other 
tidal river districts, yet Rockstone and Butukari on the Essequebo, less than 20 
miles away, were in no way affected. All these districts experienced that year 
the same abnormality in the distribution and abundance of rainfall ; but while 
on the Demerara these rains caused the production of a very unusual amount of 
suitable breeding sites at a particularly favourable season, on the Essequebo these 
same ra^ns fell on a normally flooded valley, and the seasonal Anopheline and 
malarial exacerbation followed its usual course, after the flood, quite uninfl uenced 
by abnormal local meteorological conditions. 

On the torrential flood rivers, like the Upper Demerara an<| the Potaro, 
both of which have dark acid waters, the breeding of A. darlingi *is essentially 
related to the rainfall. Where white water creeks and swamps occur permanent 
favourable breeding sites are provided* 



§66 J0tftSAl> O* BRITISH GUIANA. [Et, 4. 

Ia the Potaro and other gold and diamond mining districts, man-made 
breeding sites are of particular importance. Old gold pits filled with min water 
and other artificial collections, as required for washing and sluicing for gold and 
diamonds, may all be productive sources of A. darlingi in close proximity to the 
miners’ camps. 

Bodkin (1921) states to have found Anopheles breeding in discarded tins 
and other containers in the Potaro district. 

Both in that locality and elsewhere in the Colony, and over many years, we 
have completely failed to substantiate this claim. We have never found A. dar- 
ling i, nor A. tarsi maculatus, or A. albitarm either, breeding in containers of 
any description ranging from rainwater vats to sardine tins and coconut husks. 

Accurate statistics as regards the topographical distribution of A. darlingi 

and of Malaria in relation to the distribution of these various types of Burface 

waters in the interior are not available for the present. It is certain that the 

incidence of Malaria varies very considerably from one locality to the other. 

In our own experience, on the Demerara, swamps due to white water springs of 

low acidity were constantly associated with a high Anopheline incidence and 

with severe endemic Malaria. 

% 

Breeding Habits of A. darlingi on the Coast. 

Surface water conditions on the CoaBt are varied and different from those of 
the interior, owing mainly to the very low level of the land, and to its being 
Settled and cultivated. 

A very large porportion of the inhabited coastal belt lies below high tide 
sea level. It is liable, therefore, to tidal flooding from the sea, and seasonal 
flooding from higher lands farther inland during the rains. From such contin- 
gencies, this area is protected by sea defences abd back dams. Drainage is 
carried out by means of a very extensive net of trenches which empty themselves 
into the sea, sometimes by gravity (during low tide only), more often through 
powerful pumping stations. 

In East and West Demerara efficient sea defences exist along the shore line. 
Sea water infiltration is very small, being practically limited to leakage from the 
sea sluices at high tide. In Western Berbioe and on the Corentyne, in particular, 
vast tracks of the front lands are open to regular tidal invasion and salt water 
finds its way for a distance of some miles inland. 

Such tidal invasion, present and past, reflects itself in the salinity of the soils s 
we find that on the East and West Coast of Demerara, there is only a narrow 
strip of salt land more or less corresponding to the front pastures, which extend 
for a depth of one mile from the sea wall at the most. 

. As one proceeds towards the east the coastal salt land belt becomes progress- 
ively wider. In Western Berbice, tidal waters in many places reach beyond the 
railroad line, and salt soils are f onnd for a depth of two or more miles from the 
Shone line. » 



DUTCH LAY-OUT. ENGLISH LAY-OUT. 



Pig. 5 » — Phil of irrigation canals, drains and drainage trenches in a group of four sugar cane fields The disposition 
of the small drains within the fields varies and the two usual layouts, Dutch and English, are shown. A square mile of 
land laid out as above, in 10 acre fields, would include 16 miles of irrigation canals ; 41 of drainage trenches and 45 miles 


Plats IV. 



* Flfs* 6 & 7« — Typical' breeding Bites of A. darliiwi on the coast. Irrigation canals, sheltered by 
overhanging cane and covered w ith floating vegetation in which the larvae and pupae 
find protection from the attacks of larvivorons fish. 




MALAftU IS BHITISH O0IANA. SOi 

On the Corentyne Court, salt marshes extend a long way inland and the soils 
are xloh in soluble salt for a very considerable depth. The waters whieh collect, 
dnringthe rains, on the extensive savannahs lying aback of plantations Rose Hall, 
Albion, and Port Monrant, aS the dry weather sets in, tend to become too salt for 
irrigation purposes. This occnrs 10 or more miles inland. 

We find, in conclusion, that a very large proportion of the surface waters of 
the coastal front lands are affected by tidal invasion or by contact with soilB 
which are rich in soluble salts. The former are permanently brackish, (Coren- 
tyne front land marshes) ; the latter tend to become brackish during dry weather, 
by long contact and concentration through evaporation. (Corentyne back dam 
savannahs and front land rice fields ; East and West Demerara salt front pastures). 

The salt lands which are subject to regular or occasional tidal influx can 
usually be recognized by their characteristic vegetation : Avuenma (Gourida) ; 
Acro&ticum (Bear Grass) Sporobolus (Crab Grass) ; Pistia (Water Lettuce) and 
Cyperus (Bizzi Bizzi). 

In the inhabited and cultivated belt, natural surface waters are represented 
mainly by flooded pastures and rain water collections ; the great majority of sur- 
face water collections are made by man : these include drains and drainage 
trenches, irrigation canals, canefields in flood fallow, rice fields, ponds and 
borrow pits. 

Our plan (Fig. .'>) shows the usual lay-out of irrigation canals, drains and 
drainage trenches in cane fields. It gives an idea of the magnitude of the canal 
problem in this country. We have calculated roughly that for every square mile 
of cane cultivation (10-acre fields) there exist : 

16 Miles of Irrigation Canals. 

4.5 Miles of Drainage Side-lines. 

45 Miles of 4 ft. Drains. 

Drams and Drainage trenches rarely harbour larvae of A , darltngi probably 
in consequence of the small volume of water in the former and the frequent 
flushing in the water. We have never found this species in the 4-foot and other 
smaller drains inside the cane fields ; small open surface drains, around villages 
and estate yards, frequently harbour larvaj of A. tarsimaculatus and A. albdarsis, 
but only very exceptionally those of A. dai lingi . In the front lands, many of 
the larger drainage trenches or “ side lines ” in dry weather, tend to become 
brackish* owing to leakage through the sea sluices at high tide. 

Irrigation canals are, without doubt, the most important from our point of 
view. They receive their water supply from water conservancies or from creeks 
lying aback of the cultivation. These canals also constitute the waterway by 
which cane is conveyed to the factories for grinding. 'The- main canals are 
known as “middle walks;" at regalar intervals these give off blind ending 
branches or “ oross canals." (Figs. 6 & 7.) 



262 AOftlCtTLtfUftAIi JOURNAL OF BBtTlSfit GUIANA. [IX, 4. 

The level of the water in the irrigation system is maintained constantly high 
by pimping. In the main canals, the water is subject to fairly freqnent renewal, 
and it presents the general characters of the inland river and creek waters we 
have described, bat considerable variation exists, according to locality. 

We dad that in Western Domerara the waters from the Borassiri and 
Hababoo oonservancies and the Camooni Greek are very dark and very acid. 
(pH 4 to 5.5, sometimes even lower). In East Demerara, the sngar estates 
receive their irrigation supply from the Lamaha conservancy ; these waters are 
less acid. (pH 5.5 to 0.4 and over.) 

Blairmont and Bath receive their water from the Abary : at the pamping 
station on this river, the pH. ranges from 6.4 to 6.8; the average of 350 pH 
estimations taken in all sections of the irrigation system of these two estates, at 
all seasons and over a period of 3 years, was 6.6. Readings under 6 were 
recorded only on 5 occasions, the lowest value being 5.2; readings over 7 were 
noted sixteen times with a maximum of 7.2. 

Observations carried out at Port Mourant, on ttye Corentyne Coast, show 
similar pH values for the irrigation canals, which get their supply from the 
Caoje river. 

The sodium chloride content of the irrigation canal waters rangeB, as an 
average, from 20 to 40 milligrams per litre; except in some front land sections in 
which readings of 30 to 100 milligrams per litre were sometimes noted. 

In the middle walks the water is more frequently renewed; in the blind 
ending cross canals, it is quiescent ; during the rains the reaction in the latter 
canals is often considerably less acid than in the middle walk. In these blind 
ends, or “ bucket heads, ” floating vegetation such as floating grass ( Paapalum ), 
water hyacinth ( Pontederia ), Salvinia, and our floating mimosa ( Nepluma ), tend 
to accumulate and spread. These cross canals, overgrown by vegetation and 
sheltered as they are by overhanging cane, when the pH reaction is above 5.8, are 
the favourite breeding sites of A. darlingi. Variation in pH reaction in these 
waters, brought about by closing or opening the conservancy sluices, or by 
excessive rainfall, undoubtedly affects the distribution and intensity of breeding 
of this Anopheles in the irrigation canals. Larvae are usually absent in c&nalB 
which are kept free from floating vegetation, 

Flooded Fields : Flood fallowing is an important characteristic of the local 
technique of cane cultivation : after &ree or four crops have been taken off a cane 
field a small dam is thrown up arodfli it and it is flooded and left to lie fallow 
for 6 months to 1 year. This practice has greatly increased the yield per acre 
and is, therefore, of vital importance to the looal sngar industry. 

^lood fallowing is also a feature of unusual importance to the malariologist : 
at any time from one-tenth to one-eight of the cultivated land of an, estate is 
flooded, often in close proximity to estate villages. For the first few months 
after flooding a considerable amount of fermentation occurs from’tthe submerged 



Plate V. 



FI*. 8. —Flooded fields lying fa 1 low, \s hen co\cred with floating and vertical vegetation and favourably 
may be productive source* of A dai hngt , 



Fig. 9.— Rice fields situated beyond the salt coastal front lands, and sheltered by trees and scrub, are 
breeding sites of A dvrhnqu 




Plate VI, 



Fig, 1 0. — Open, windswept rice fields in the Balt coast front lands are fa\ounte breeding sites of A , tammaculatus , but only very 
exceptionally harbour A. darhngi . 



ItlLAftU IN BRIfiea GUIANA. 


cane tops and stamps s the water is brown and has a distinct odonr ; vegetation is 
scarce. At this stage we have never found flooded fields harbouring Anopheline 
larvae. 

After three or four months vertical and floating vegetation appears and 
rapidly spreads (mainly Paspalum, Pontederia , Salvinia, Neptunia and 
Limnocharis). The waters become clear and their pH ranges usually from 6.2 
to 6.8 ; the rains have an important part in bringiog about this change in the 
characters of the waters. At this stage flooded fields often become very pro* 
d active sources of A. darling i. In gome localities we have completely failed to 
find larvae of this species in spite of apparently favourable conditions. 
Abnormally high salinity of the waters (100 milligrams per litre) or lack of 
shelter and general situation and exposure of the field sometimes explain these 
negative findings (Fig. 8). 

Rice Fields : Rice is cultivated throughont the coast, aronnd and in the 
immediate neighbourhood of most villages, on sugar estates and on some of the 
creek savannahs. According to locality this cultivation is dependent on the 
rainfall, on the irrigation system of sugar estates or on the seasonal creek 
floods. Planting is done between March and June ; the fields are under water 
from May to August ; reaping takes place in September and October. Usually 
only one crop is planted and after reaping the fields are left to themselves till 
the following season, most of them being flooded during the Autumn rains. 

When the growth of the rice is well advanced rice field waters are usually 
clear and light brown in colour ; pH ranges from 6 to 7 ; their content in soluble 
salts varies within wide limits : in most front land fields tho sodium chloride 
oontent is frequently well above 100 milligrams and sometimes amounts to 
several grams per litre ; further inland it is usnally low, 15 to 50 milligrams. 

The full grown rice plant offers good protection to mosquito larvae at its 
base, in between the stems. Larvae of .1. tarsvngculatus are practically always 
present and abundant. A. albitarsis occurs when the salinity is low. Under 
the latter conditions .4. darlingi may ,be found, sometimes in large numbers, 
when the rice fields are sheltered by surrounding trees and vegetation which 
form wind-screens and offer a certain amount of shade. This species is 
practically never found in the rice fields of the open, windswept front lands as 
exist on the East Coast, north of the sugar estates and, more particularly, in 
Eastern Berbice. (Figs. 9 and 10). 

Borrow Pits : These exist in great numbers the length of the coast along 
the rail and public roads ; scores are dug every year for the preparation of burnt 
earth. Fortunately they are nearly all located in the windswept, salt front lands 
and though very productive of Culex mosquitoes and A. tarsimacvlatus they 
form unlikely breeding sites for A. darlingi . During heavy rains and where 
suitable shelter exists borrow pits also may become dangerous breeding sites for 
A. darlingi * 



204 * AGRICULTURAL JOURNAL OF 6R1T i ISH GUI AKA. £lX, 4. 

On sugar estates abandoned factory sites, with bush corned foundation 
pits and obsolete canals, often present excellent conditions for the breeding of 
the dangerous malaria carrier. (Fig. 4). 

Ponds : These are particularly common in villages where, in the absenoe of 
irrigation canals, they are used for storing rain water for domestic purposes. 
A. taraimaculatus is nearly always present ; A. darlingi may occur when the 
water is clear and sweet and if suitable shelter exists. 

Flooded Pastures : Beyond the coastal salt land belt, flooded pastures when 
sheltered and rich in vertical and floating vegetation, are dangerous ; the same 
may be said of the bush covered rain swamps which collect on sand-reefs and 
other abandoned lands. 

In the salt front lands, where A. darlingi is usually not found breeding, this 
species may occur, sometimes in considerable numbers, during heavy and 
persistent rains which affect both the physio-chemical characteristics of the 
waters and atmospheric humidity. 

From this brief review it will be noted that a very , large proportion of the 
water collections which favour the breeding of A. darlingi on the coast are man- 
made and that they are essential and, therefore, unavoidable factors in the basal 
agricultural industries of the Colony, sugar and rice. 

Most of these surface waters, (irrigation .canals, flooded fields and many rice 
fields) are not dependent on seasonal factors such as rainfall and floods ; they 
are permanent, and as such offer, the year around, favourable conditions for the 
breeding of Anopheles. Though season evidently still plays an important part 
in the intensity of Anopheline breeding, we have found that A. darlingi on the 
coast can be collected, both in its adult and developmental phases, throughout 
the year. In the interior we observed this to occur only in proximity of white 
water seepage swamps which offer permanent and suitable breeding sites. This 
is evidently the reason why on those parts of the coast which are subject to 
endemic malaria, the seasonal incidence of this disease is very much less clearly 
defined than in the interior. 

Both in the interior and on the coast our findings tend to demonstrate that 
the breeding of A . darlingi is restricted to certain types of surface waters. 
This species has a preference for water collections of considerable size. There 
evidently exist certain characteristics of surface waters and soils which are not 
congenial to this species and which, therefore, tend to limit its dispersion. We 
believe that the following are some of such limiting factors. 

Reaction of Surface Waters : A. darlingi is only exceptionally found in 
waters with a pH value under 5.8; the optimum range is from 6.2 to 6.8. 

A^Oane Grove, in spite of general conditions which would at first lead one 
to expect the existence of severe malaria, we have found this disease only mildly 
endemic (spleen rate : 16.1% and parasite rate 15,9% in 1937). The soil in this 



MALAftIA t » BIUTISft GUtAHA. 


205 


locality is exceptionally acid. In April this year we found the pH of irrigation 
canal waters ranging from 5.2 to 5.4 ; in some stagnant drainage trenches we 
obtained readings as low as 3.5. We failed completely to find adult A . darlingi 
in the houses or its larvae in any of the surface waters, in spite of the fact that 
this species was at that time abundant all along the East coast. 

At Wales, an estate with a particularly bad malarial reputation, the incidence 
of this disease has shown a very distinct drop since 1934, coincidently with the 
opening of a canal from the Camooni Creek to the Hababoo conservancy which 
supplies the irrigation canals of this estate. Camooni waters are very acid 
(pH 4.26 to 4.47 in April 1938). In August 1937, (with the Camooni and 
Hababoo sluices open) in a search lasting several days, we completely failed to 
find larvae of A . darlingi in the irrigation canals of this estate (pH 5.2), but we 
found them common in flooded fields (pH 6.2 to 6.6). In April this year, during 
heavy rains, with all the conservancy sluices shut, we found only a few larvae 
of this species at the bucket head of a cross canal (pH 5.8); at the same time in 
flooded fields and in the game locality (pH 6.6) larvae could be collected at 
every dip. 

In the interior a very large proportion of surface waters are strongly acid 
and we believe that from a malariological standpoint they are not dangerous ;we 
have, in fact, successfully controlled productive breeding sites by opening them 
up to tidal invasion by acid river and creek waters. 

Salinity ; A . darlingi is only rarely found in waters which contain over 
100 milligrams of sodium chloride per litre* On the Berbice estuary in 
three years we made only one such observation, the sodiutn chloride titro being 
184 milligrams per litre.* The usual range is 20 to 60 milligrams, but in the 
laboratory we have raised this species, from ovum to adult, in water containing 
800 milligrams per litre. 

On the coastal front lands and on the Oorentyne in particular very extens- 
ive tracts of marshes are permanently and definitely brackish ; other vast areas 
of surface waters become so in the dry weather tfirough contact with salt soils 
and evaporation. Most of the rice cultivation in the Berbice front lands falls in 
this group. All such waters, as not productive of A , darlingi , can be overlooked 
in the carrying oitt of an aatbmalarial campaign, 


•Since the present articlo was written, wo have found d. darlingi breeding in water with 
a sodium chloride coutent of slightly over 3 grams per litre, at La Bonne Intention, on the 
Bast Coast. 

Larvae and pupae were found in a canal communicating with the damtned off terminal 
portion of the main middle walk which, during the rains, is used to blow off to sea, through 
a sluice, excess water from the irrigation system. 

When this canal is stopped off from the main irrigation system as at present, at high tide 
salt water leaks through at the sluice gate. m 

We have found that the salinity in this canal and at the same spot where the larvae were 
discovered varied within wide limits, in the couise of only 5 days the sodium chloride falling 
progressively from 3.(550 to 0.400 milligr. per litre. 

The breeding of A . darlingi in water of such high salinity Certainly remains a very 
Unusual oecurxtnce. 



S06 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


ClX, 4. 


Atmospheric Humidity : This too we believe is an important factor which 
limits the range of A. darlingi : the adult of this species is very susceptible to 
desiccation and exposure to the strong coastal breeze rapidly kills it. 

Some localities, though presenting apparently ideal surface waters, under 
ordinary meteorological conditions are practically free from A. darlingi and 
from endemic malaria. Plantation Bath is a good example ; the canals and 
flooded fields of this estate receive their waters from the same Abary pump 
which supplies Blairmont, a notoriously malarial locality. We studied these 
two estates comparatively for three years (1034-1936) and came to the conclusion 
that the drier atmosphere at Bath was responsible for the absence of A. darlingi. 
It should here be remembered that this mosquito is a strict night flyer and 
mainly a native of equatorial forest regions where the night atmosphere is 
more or less constantly saturated with moisture. 

We attribute the habitual freedom of the Corentyne coast from A. darlingi 
and endemic malaria to a relatively higher atmospheric dryness and to the sal* 
inity of the surface waters and soils throughout the inhabited belt. 

The well defined seasonal malarial epidemics which have occurred at Bath 
and on the Corentyne coast following the very exceptionally wet seasons of 
1937 and 1938 tefld to confirm our views. 

The factors which we have listed as controlling influences on the breeding, 
and therefore on the dispersion of A. darlingi , exercise no similar influence on 
the other local common Anopheles. Thie is particularly the case for A. tarsi - 
maculatus which presents the most remarkable latitude in the choice of its breed- 
ing sites : we have found this species breeding actively and evidently flourishing 
in waters the pH of which ranged from 4 to 7.8 and the sodium chloride content 
from 0.005 to 28 grams per litre. With such extraordinary adaptability practi- 
cally all surface waters of this Colony are suitable for this species if cover is 
provided in the form of vegetation or floatage for the protection of the larvae 
from their natural enemies. Evidently the control of this species on the coast- 
lands of Guiana would be a very arduous, not to say hopeless, task. Fortunately 
this control is not required as this species locally does not act as a carrier of 
Malaria. 

We have thus concluded the study of the entomological aspects of the local 
malarial problem in its principal lines. 

Our findings are encouraging as only a single kind, out of the several local 
Anopheline species, emerges from this investigation definitely indicted with the 
transmission of malaria in this Colony. We have also fonnd that A. darlingi 
has certain selective breeding habits and that its range of flight is equally subject 
to certain limitations. 

These findings infinitely simplify the malarial prevention problem, for they 
allow til to direct our effort against well defined objectives with a good knowledge 
of the vulnerable points in the enemy’s defences. 

{To be Continued) ' 



THE GEORGETOWN BOTANIC GARDEN. 

SOME NOTES ON ITS EARLY HISTORY. 

BY 

E. B. MARTYN, B A„ A.X.C.T A. 

Government Botanist & Superintendent, Botanic Gardens. 


In the latter part of the 10th century, the formation of Botanic Gardena or 
Botanic Stations was encouraged throughout the Colonies. In the West Indies 
the Gardens at St. Vincent, the forerunner of them all, and those at Trinidad, 
were already long established. The object of such gardens was primarily to 
encourage the introduction of new crops, and Sir Joseph Hooker, Assistant 
Director and later Director of Kew from 1855-85, took a keen interest in them. 
They were in many cases, including British Guiana, the forerunner of later Agri- 
cultural Departments and Experiment Stations. 

It is not quite clear who was chiefly responsible for the initiation of the 
Georgetown Garden, but in 1878 the Combined Court voted a sum of $240,000 for 
the establishment of a Garden that was to be both a recreation ground for the 
citizens of Georgetown as well as a site for the experimental cultivation of plants. 
The area chosen for the new Garden, some 163 acreB in extent, was part of the 
back lands of the old Pin. Vlissengen, and was purchased for a sum of 952,140.95. 
It was selected as being close to the city, its position in the angle of the Lamaha 
Canal also being advantageous for purposes of irrigation. Apart from this how- 
ever, the site had little to recommend it, as the land had heen abandoned for 
many years, and was trampled by cattle and largely overgrown by bnsh. In add- 
ition the drainage trenches were choked up, and the removal of earth from 
various places had added further to the swampy nature of the ground. 

The task of designing the new Garden was ‘'entrusted to Mr. Prestoe, then 
Government Botanist in Trinidad, who visited the Colony for this purpose in the 
Autumn of ’78. On seeing the site he was immediately struck 1 by the two 
avenues of Oronoque trees, relics of the old estate, the one running down the 
line of the middle walk, from front to back of the estate, the other crossing the 
former at right angles, near the front of the estate- On these two avenues, which 
were to be left almost untouched, the plan of the new Garden was based. 

Mr. Prestoe’s plan was forwarded to the Governor, (C. H. Eortright, Esq., 
C.M.G.) at the end of November, 1878, with a request that the area destined for 
the nursery should be temporarily fenced as early as possible, and got ready for 
tho raising of young trees and shrubs. The Garden was to be under the manage- 
ment of a Board of Directors, and Mr. Waby, who had been Assistant Gardener 
in Trinidad, was appointed to bo Head Gardener and to supervise the carrying 
out of the plan until the arrival of the new superintendent, Mr. G, S. Jenman, 
from Jamaiba, where he had been in charge of the Castleton Garden. 



308 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4. 

Mr. Waby and his family arrived in the Colony at the end of December, ’78, 
bringing with them a number of young plants from Trinidad, and Mrs. Waby has 
left a good description of the conditions met with on their arrival. 0) After 
being taken by Mr. Tinne, Chairman of the Directors, to see the site of the new 
Oarden, Waby returned to his hotel horrified at the morass which he was 
expected to tackle, and wished very much that he had Stayed in Trinidad. It 
was a further disappointment to him that the Gardener’s house which he was 
expecting had not even been begun. For the first three years he and his 
family lived in a small house (the old Government Laboratory) at the top of 
Brickdam which for some time also provided nursery accommodation, potting 
sheds, and storage room for the Garden. 

The first essential of the Garden was to obtain proper drainage, and to build 
up the main avenue. The whole level of the front Garden, which was to be tile 
drained, needed to be raised, the old middle walk navigation trench had to be 
filled in, and side lines dug. Prestoe had planned a series of lakes which were to 
give drainage and provide earth to ‘fill in dips and make undulating banks.’ The 
roads, he considered, if built up and ‘round-ridged’, using r the subsoil mud, would 
need very little surfacing ( sic ). As work proceeded, however, it was found that 
more lakes than originally planned for were required, first to raise the level of the 
ground sufficiently quite apart from making undulating banks, and also to pro- 
vide large quantities of burnt earth to cover the avenue and the side paths, The 
transport of the earth was facilitated by the use of a portable railway, first hired 
from Booker Bros., and later purchased.* 

Work on the new Garden was begun on January 2, 1879, and the first meet- 
ing of the Board of Directors was held at the Royal Agricultural & Commercial 
Society’s rooms on February 1. The Honourable J. E. Tinne was Chairman, the 
other directors being the Honourable H. T. Garnett, the Honourable A. F. 
McFalman and W. H. Campbell, Esq. (the last named eventually became Chair- 
man in January, 1883, and always took the greatest interest in the Gardens until 
his death in December of the same year). At the meeting Waby read his first 
report, and it waB decided that each director in turn would supervise the work 
for one week. It may be noted that at most meetings in the ensuing years not 
more than two Directors were usually present. 

The new Government Botanist and Superintendent of the Gardens, Mr. G. 
S. Jenman, arrived in the Colony in August, 1879. Almost immediately after his 
arrival he set out on a collecting expedition up the Corentyne River with Mr. 

(l) Eleanor S. Waby ‘Forty Years’ Life in Tropical Gardens', Timehri, Vol. Ill, 3rd. series 
No. 2, 1915, p. 285. 

* This railway had a long and varied history. In December, 1883, when no longer required 
at the Gardens, it was temporarily lent to the Public Works Department, end no further men- 
tion of it appears for 34 years. In 1917 however, the late Sir John Harrison, Director of 
Scienoedkia Agriculture, having presumably found the letter relating to the original loan in an 
old fitawrote to the Public Works Department and asked for the return of the railway belonging 
to the Botanic Gardens, and which had been temporarily lent! The Director of Public Works 
replied however, that no trace of it could be found, ana that it had probably been used on the 
sea defences, - 



Plate VII. 



Fxu 1. The Entrance Gates and Lodge to-day. 







THB OTOBGBTOWN BOTAJTIC GABDBH. 


209 


im Thurn, who had already arranged to make a journey in this area in his capac- 
ity as Cnrator of the Museum, and it was not until November that Jenman 
returned to town and took up his duties at the Gardens. From that time until the 
day ef his death — rather more than twenty -two years later — hia energy and keen- 
ness provided the main driving force to complete the laying out and manage the 
subsequent maintenance of the Gardens. Not many people in the Colony today 
remember Jenman well, but from the records of his correspondence and minutes 
it is possible to form a picture of him. A man of strong character and quick temper 
is revealed in the copies, in his own hand, of a number of acrimonious missives, 
both to the Directors and the Government Officers to whom he was responsible, 
and also to his subordinates; but these records also make plain his great insight 
into all matters horticultural, and his constant wish that the Garden should con- 
tinue to improve and fulfil all of the objects for which it was laid out. After he 
had laboured for two years, the Directors and himself received the highest praise 
from Sir Joseph Hooker on the progress made, and throughont his career 
Jenman received a number of well merited commendations on his work, both as 
Botanist and Superintendent of the Gardens, from those best qualified to judge 
in either sphere. 

One of the matters requiring early attention was the housing of the Superin- 
tendent and the Head Gardener ‘on the spot’. On his arrival Jenman took up 
residence at the old Tower Hotel, and within a month or two his claims for cab 
hire to and from the Garden were already involving him in arguments with Gov- 
ernment. Waby, as we have seen, was temporarily housed in very inadequate 
quarters at the top of Brickdam. It had been originally intended to build the Head 
Gardener’s house on the piece of land opposite the Garden, now occupied by the 
Department of Agriculture, but this idea was abandoned, and it was decided to 
build both houses inside the Garden. The Wabys’ honse was finished at the 
beginning of 1882, and they moved into it in February. A bungalow, built at 
ground level, with more attention paid to its outward appearance than its internal 
accommodation, it was a most unhealthy and uncomfortable residence. However, 
it underwent a number of subsequent changes, 'which included raising it on 
pillars, and altering the roof, which had originally sloped to within 3 feet of 
the top floor. Today it is used as the Chemical Laboratory of the Department. 

The building of the Superintendent’s house (now the residence of the 
Director of Agriculture) involved Jenman, the Directors and the Public Works 
Department in prolonged controversy. First there were delays in acceptance of 
the plan, then in erection of the building, upon the completion of which Jenman 
demanded a number of alterations, only some of which were provided. Finally, 
though the building was finished in December; 1882, and the Government 
Botanist’s office on the ground floor was used from that time, Jenman could not 
or would not take up his permanent residence in the building until the middle 
of 1883, as prior to this there was no proper bridge giving direct access to the 
house and the only other means of approaching his new home was acroBS the 
still unfinished Garden, from the main entrance gates of the latter, 



210 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 4. 


In the meantime, other construction work in the Garden had been going 
on. The entrance gates, decided upon in February, 1880, were ordered from 
England, erected in January, 1881, and have not been changed since. The 
Lodge beside the gates was also built in 1880, with a front room where the 
Directors could hold their meetings, and accommodation for a watchman. It 
originally had a shingle roof, only replaced by iron sheets in 1932. This build- 
ing was designed by the Honourable J. Brummell, Sheriff, who had become a 
Director in February, 1879, and in May succeeded Mr. Tinne as Chairman, and 
in whose office in Brickdam Directors’ meetings were held from that time until 
the Lodge was ready. Mr, Brummell was one of the keenest of the Garden's 
early supporters, and bis death in December, 1881 was a great blow. The 
present Bandstand was eventually erected to his memory in 1889 and is certain- 
ly a more worthy memorial than the drinking fountain first suggested as suitable 
for this purpose. (It is of interest here to note that permission for the Militia 
Band to perform in the Garden was first obtained in May, 1883). 

Bnt to return to the Garden itself, the drainage and irrigation of the land 
provided a series of difficult problems. As regards drainage, it was decided 
that the Front Garden — some 20 acres in extent, should be tile-drained. Large 
underground drains made with concrete slabs were laid down on each side of 
the main avenue, and into these emptied the water from 40,000 feet of tile 
drains. The latter were made at Pin. Montrose and laid in 1879 by Chinese 
labourers from the estate, who were experienced in work of this nature. Five 
years later they had become choked, and had to be cleaned, work again carried 
out by the Chinese, and they once more had to be cleaned in 1889. Eventually 
it was realised that such a form of drainage was not suitable for local conditions, 
and after Jenman's death the open drains at present in existence were made. 

To get the water away from the land, the Croal Street trench, which formerly 
provided the only outlet, was not sufficient, and a tunnel was made under the 
Vlissengen avenue to connect the north side line to the North Road trench, 
the responsibility for deepening this and the South Road trench eventually being 
amicably settled with the Town Council. Drainage however continued to be 
poor, especially during wet weather, when the ground remained water-logged for 
days on end, and in consequence the Superintendent’s and Gardener’s 
houses became most unhealthy. In 1889, a drainage pump was put in at the 
north western corner to drain the Flower Garden ; it was transferred in 1899, 
to drain the Experimental Fields,* and later removed by the Public Works 
Department. 

Irrigation received early attention, and in 1882 a tall iron tank and pump- 
ing engine were erected, and connected to a series of pipe lines throughout the 
front Garden. Subsequently, it was found difficult to obtain sufficient preBBnre 
in the tank, and irrigation by this method was never very successful. In later 
years, open irrigation channels were used, and recently the original pipe lines, 
the n&jority of which were found to be still in sound condition, have been in 
great part connected to t he town water supply, whereby a suitable pressure for 
*See footnote on page 211. 


Plate IX. 



*h»tol [Dr. B. B. Dahlgren. 

Fiu. 3. — The “Oronoque Avenue,” now the Central Avenue through 

the Park Lands. 



Fig. 4— The Bandstand and Flower Garden 


«n ewumcrn* sordine oaso*. su 

watering k obtained, and this can be much more effectively carried oat. The 
irrigation tank was dismantled and removed in 1936 . 

The first 18 months in the life of the Garden was entirely taken up with 
preparation of the land, and The work was somewhat hampered by very wet 
weather in 1880. Planting, however, began in the middle of the latter year, 
the oval, in the middle of the avenue, being the first area planted, after which 
followed the border along the Vlissengen Road, the ground abont the lodge 
(including the Eucalyptus trees which stand behind it today) and the line of 
Bamans along the northern side of the Garden. As early as 1881 Jenman 
remarked on the surprisingly rapid growth already made by the majority of 
the new trees. Before the planting of any of the borders, however, the first 
part of the Garden to be laid out had been the nursery, which was divided into 
squares, surrounded by a Cherry Hedge (which is there still) and provided with 
a temporary progagating shed, which remained until 1894, when it was removed, 
having been replaced in 1890 by a more permanent erection, part of which 
remains today. The sale of plants began in 1883. Amongst early plant intro- 
dnctions raised were a number of grafted Mangoes and Litcheee, obtained from 
Calcutta on an immigrant ship, and some canes from Honolulu, several of which 
survived the 2 months’ journey despite the fact that they had been packed dry, 
with the ends sealed, and formed the basis of the large collection of Sugar Canes 
that were later used for Jenman and Harrison’s* researches on this crop. 

The plan of the Garden included the Vlissengen Road Avenue, which was 
to be planted with Saman trees that had been raised at Waby's house. The 
construction of the avenue entailed considerable labour, as to give it the 
necessary breadth the old trenches bordering the road had to be filled in and 
new ones dug further out. This was pai t of the firat work undertaken, thongh 
the avenue was not planted until January, 1881. Some difficulty was experienced 
as the young trees grew up to prevent their leaning with the prevailing wind, 
and their appearance even today shows that in not every case was this tendency 
overcome. 

The Central Avenue to the back of the Garden, or Oronoque Avenue as it 
was then called, was planted in 1881, shortly after fhe Vlissengen Road Avenue. 
The Directors originally decided to make this main avenue representative of the 
principal forest trees of the Colony, but as many of these 1 would not thrive on 
the Coastland, and as another alternative, namely a selection of fruit trees, would 
have proved too great an incitement to petty pilfering, it was finally arranged 
to use a selection of large growing tropical trees, the majority being American 
species. The lower half of the Avenue was made 20 feet wide, and bordered by 
trenches which were to act as reservoirs in dry weather and take off the surface 
water after rain. The upper half was originally only 10 feet in widt h, and the 

*Mr. Harrison aa he then was. arrived in the Colony in 1889 as Government Analyst in 
place of Mr Francis who had died. The drat cane cultivation was carried out.on an atea of 
4 acres, outside the south-eastern corner of the original Garden, and now forming the soathern 
field of the Experiment Station. The field of tho present Station immediately south of the 
avenne was taken into cultivation in 1899 when the work on cane was extended. The field to 
the north of the avenue was cleared and taken in for rice cultivation circa 1903, 


812“ „ AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4. 

ground through which it passed was left for some years in its original wild state, 
with the idea that it might be used for planting trees suitable for timber or fire- 
wood, This idea was never carried out, and eventually it was taken into cultiva- 
tion to form the experimental station. In the early days of the avenue, the Or- . 
onoque trees ( Erythrina glaum) formed its chief feature, though they have 
gradually fallen, until today only two or three creeper covered relics are left. In 
the drought at the end of 1887 the flowering of these trees was a remarkable 
spectacle, as they were crowded with blossom, and at the same time all the 
foliage was shed, which is not typical of this species of Erythrina . 

Beside the Central Avenue, the two Serpentine Roads were laid out, but 
were not surfaced, or connected by bridges to the main avenue for some years. 
The Hippanai Trees ( Parkin pmdula) originally planted along them, did not 
prove a success, and the Pithecellobiums and Palms bordering these avenues 
today were not planted until 1888. 

In addition to these avenues within the Garden however, it was originally 
intended to make a drive (36 feet was the width first suggested) around 
the outside of the whole area, and with this, end in view the D’Urban 
Park gap was extended in 1881, chiefly with earth from the new south side 
line.* After this the next operation was to have been the making of a drive 
on the northern side, bordering the Lamaha Canal, but owing to the difficulty 
of raising the surface of this road to be high enough above the level of the 
Lamaha in wet weather, the idea was never carried out, and the North drivo 
was not built, this strip of land being planted instead with shrubs and trees. 
In 1882 a strip of land north of the canal was bought from Pin. Bel Air, and 
planted with quick-growing trees to form a shelter belt for the Garden, which 
land was subsequently given to the Town Council in 1925 and cleared to form 
the site for the new Water Works and Pumping Station Buildings. 

By October 1882, the original amount of $240,000 voted for the establish 
ment of the Garden was nearly finished, and Government apparently considered 
that the new venture was proving rather unduly expensive, for the Directors 
were asked to curtail expenditure and told that in future the Garden must 
be run on an annual maintenance vote. When asked however, what he 
considered the expenditure would be in 1883, Jenman’s estimate totalled 
$23,432 ! 

In May 1883 Jenman began to attend Directors’ Meetings regularly, and in 
June the Directors were relieved of the financial business of the Garden and 
Jenman had to requisition Government for money and account to them for its 
expenditure in the usual manner of a Government Department, though the 
Directors still acted in an advisory capacity. The relative relationships between 
Government, the Directors and the Superintendent appear to have been rather 

*Itmay be noted that the D’Urban Park Race Club Stand was from the beginning left out- 
side%he Garden, cut off by a detour in the side liue trench as it exists today. Other stands 
belonging to the club, which stood formerly on the land leased to the Directors, were removed 
at their request when the land was taken over. 




PlATE XI, 



Fit,. 5. — The Iron Bridge o\er No. 2 Lake. 


Plate XII, 



Fifr. 6,— Jenman*«« House and Herbarium. now the residence of the Director of Agriculture. 


THE GEORGETOWN BOTANIC GARDEN. 


213 


vague, but when in 1888 the Directors were informed that they were to have no 
farther control over the Superintendent or the finances of the Garden, the 
Chairman and two other Qireotors threatened to resign, and the two latter in 
fact did so. By this time however. Directors' meetings were only held at very 
infrequent intervals, and in May, 1892, appear the last recorded minutes of a 
meeting. 

As commonly occurs with concerns of this nature, the amount of money 
provided for the upkeep of the Carden was often less than the ambitions of 
those responsible for its appearance demanded. Thus in 1886, when a further 
loan of 820,000 for the completion of the Park Lands area was exhausted, and 
no provision made for their upkeep, Jenman was horrified to discover, on his 
return from leave, that the vote for maintenance of the whole Garden had been 
cut (by a majority of 1 on the division) from 810,000 to 87,500. He had previ- 
ously stated that 810,000 was inadequate and considered 815,000 the minimum 
necessary for maintenance. As a protest, declaring at the end of the year that 
he could not maintain the Flower Garden with the money available, he dis- 
charged all hands during December and left the area unattended, and in 1887 
allowed the appearance of the Garden to become so bad that a reprimand was 
reoeived from the Governor. In the ensuing year however, the vote was 
increased by 82,000. 

Glancing through the correspondence, minutes of Directors' meetings, and 
other papers concerning the Garden, of which copies remain, we get some inter- 
esting and amnsing insights into the affairs of sixty years ago. There is a note 
on the price paid for labour in August ’79 — Foreman 64cents per day, Bhovelman 
32-40 cents, women 24-32 cents. In May ’80 a clock and bell were requisitioned, 
to ensure more punctuality over working hours. In '81 the closing of the 
Garden to visitors after the official hours was strictly enforced. In *82 we find 
one of the Directors involved with Jenman in violent conflict, conducted mostly 
with the pen, over a matter of some coffee seedlings which the former had 
obtained from the Garden while Jenman was on leave at a price which the latter 
considered too low. In the end, the Director in question resigned, and after a 
series of parting shots from all concerned, the action was broken off. In '83 
Jenman was given a riding mule to use in the Garden and Waby had already 
been supplied with a pony in 1879,* but the former’s subsequent application for 
a horse and waggon was refused. In 1883 also there were constant bickerings 
with the Public Works Department concerning the engineer in charge of the 
irrigation engine. This individual, described as a Petty Officer of the Public 
Works Department, was under the latter Department’s orders and would brook 
no interference from the Garden Superintendent. The result can be well 
imagined. 


* This animal performed yeoman service for Government until Jane, 1899, when Waby 
reports that ‘on Tuesday last it fell beneath me, all of a heap', and asks for another one, enclos- 
ing a certificate from the Government Veterinary Surgeon to the effect that the pony in 
suffering from ’stule deoay'. 




814 


AG&ICULTOUX. JOtfMUL Of WSttftXB, OMASA. [it, & 

la Jane ’83 the Georgetown Bicyele Oiab applied for leave to make a brack 
250 yards round in the Garden, for use of members. Though the application 
was at first refused, iu the following year it reoeived the Directors’ support, but 
nothing seems to have come of it. In ’84 the Tramway Company applied to run 
their vehicles from the terminus in Croal Street up to the end of that street 
and some 409 yards along the southern dam (i.e , the D’Urban Park Gap), and 
this being objected to, applied in ’85, to come to the Garden main entrance. 
This also wa 3 refused, though it was suggested they might stop in the Ylissengen 
Road opposite the top of Charlotte Street, but the proposal was apparently not 
followed up. 

About this time we note a complaint by the Superintendent on the stealing 
of plants from the Garden, usually by people who Bhould know better. In ’84 a 
Horticultural Exhibition was held in the Garden, and in '85 there is an interest- 
ing note that the Georgetown Cricket Club had asked for assistance in planting 
a cherry hedge round their new ground. In 1885 also the Iron Bridges to cross 
the first two lakes, obtained from England in ’82, were at last erected after many 
delays. The Sun Dial in the avenue had also arrived 'in ’83. 

In the early days of the Garden the traffic consisted chiefly of carriages, 
but in the nineties we find this falling off, and the number of bicycles increasing, 
somewhat to the annoyance of the Superintendent, who writes as follows in his 
report for 1896-97 : 

“Cyclists have created quite a demoralisation ; they care not for Rules 
or remonstrances, and any kind of control is simply out ot the question. 
My attention has been repeatedly drawn to the fact by other visitors, 
entreating me to keep them entirely out of the place, and I know myself 
of no gardens anywhere at home that cycles are allowed into, they being 
confined everywhere, when off the street or high-road, to cinder-paths 
of their own, in enclosed grounds, for practice or exercise ; and here, 
also, they should be as absolutely excluded from the gardens. To all 
other visitors they are an anxious nuisance, more particularly the silly 
girls and giddy youths who appear carried away, particularly on Sunday 
mornings when persons would like a quiet stroll, with reckless, aban- 
doned exhilaration and levity, unable to control their conduct. ” 
and again in the Reposrt for 1897-98 : — 

“ Wheel Traffic . — Since 1894 there has been an unfluctuating steady 

annual decrease in the carriage traffic in the gardens, due, 

I believe, ...... to the still growing popularity of eycling with young 

people of both sexes. Except in collisions and spills, there is an independ- 
ence in bike riding that young people who have not yet begun to realise 
the responsibilities of life are greatty taken with and that fills their minds 



Plate XIII. 



Photo] f ,>r H K I>ahlpren. 

Fu„ 7 — Lotus LiUe& in a Lake m the Park Lands. 



Tflfi (M0B6BT0WN SOTUflC GARDEN. 


215 


with cheerfulness Here is the record of the carriage traffic 

since 1893-5 : — 

Total carriages entered. Mean daily. 


1894-5 

12,044 

33 

1895-6 

10,500 

29 

1896-7 

9,908 

27 

1897-8 

8,200 

22 

1898-9 

7,715 

12 


Th? 3 e figures are particularly interesting. They show that since 1894 

when the cycling interest and zest had taken on well, the carriage 

traffic in the gardens has fallen 4,329 entries ” 

During the ensuing years however the number of cyclists steadily increased and 
the carriages still continued to fall away. 

Wo may now turn to another aspect of the Garden. In 1889 a Zoological 
Committee was formed, which in fact consisted of the majority of the Directors 
together with the Superintendent, and arrangements were made whereby a 
number of indigenous animals, including deer, waterhass, tapirs, etc. were kept 
in the Garden. A good many losses were sustained, but new additions were 
made to take their places, and the collection was kept up for many years. It was 
in 1892 that the first pair of manatees was introduced to the lakes, and by 1896 these 
animals had cleared the lakes of their natural vegetation to such an extent that 
they had to be hand fed as they are today. With regard to the lake vegetation, 
it is interesting to note that the Lotus Lily ( Nelumbo naeifera}, now plentiful 
in the Garden, and to be seen in trenches in many parts of the coastland, was 
first introduced in 1882, only one plant surviving from the seed planted. Two 
other interesting introductions to which attention may be drawn were the 
Double Coconuts (Lodotwa maldivica), first obtained from the Seychelles and 
successfully germinated in 1893, and the Cajeput Tree ( Melaleuca h’ueadcndron), 
seed of which was first sent by Sir Ferdinand von Mueller from Australia with 
a glowing description of the value of the trees to dry up swampy land. 

Mention must bo made of several subordinate officers who played a part in 
the upbringing of the Garden. At the outset, Mr. Waby was assisted by a 
planter, Mr. Howell, who had charge of the task work. In 1883 the latter 
resigned and his place was taken by an assistant Gardener from Kew, Mr. Derry, 
who three years later was transferred to Malaya, making way for Mr. Ward, 
whose long and zealous services for the Garden only ended with his retirement 
in 1926, after forty years’ service. 

On Mr. Ward’s arrival, his duties included taking charge of the meteoro- 
logical records, which were kept in great detail, a set of instruments having 
been obtained from Kew in 1879, to which additions were made later. In this 
latter connection, it is interesting to note some periods of abnormal weather 
that affected (he Garden in the first two decades of their existence. In 1884*85 



§16 idRiotiLttmiL JotmtrAt t>i vmiai GtiiAku. fix, L 

there was a drought ; the years 1889*1893 were five consecutive abnormally wet 
years, culminating with a record total of 135 inches in 1893 ; in the latter part 
of 1899 there was another drought, only 52 inches falling during the year, but 
it broke dramatically with the close of the century, on Old Year's night. 

The first epoch in the history of the Garden closes with the death of 
Jenman on February 28, 1902. He had lived to see his creation successfully 
established, and had left a lasting memorial to his labours. Principally owing 
to his dislike of travel by sea, which seems to have caused him extreme illness, 
far beyond normal sea sickness, he had not left the Colony since 1886, even 
refusing the Governor’s request that he attend Agricultural Conferences in 
Barbados in 1899 and 1901, so that his Garden had indeed become his home. 
He was buried near it, in St. Sidwell’s Church yard. Today, visitors are 
reminded by the clock on the Lodge and a tablet below of the man to whose 
inspiration they chiefly owe the Garden which they are seeing. 



a water Rat (hoplochilus sciureus berbicensiS 

Morrison- Scott) DAMAGING SUGAR-CANE IN 
BRITISH GUIANA. 


BY 

L. D. CLEARE, k.r.ent.s., 

Entomologist, 

Department of Agriculture, Britith Guiana, 


INTRODUCTION. 

Rats are of common occurrence in the cane-fields of British Gaiana and from 
time to time cause damage to an extent sufficient to necessitate special measures 
being taken againBt them. These increases, however, are usually of short duration 
and more or less limited in extent. On most sugar estates also a few men are 
more or less regularly employed as rat-catchers, who hunt these animals with 
dogs. In former years it is evident that rats were considered important enough 
to cause the mongoose to be imported from the West Indian Islands. 

Just what species of rats occur in the cane- fields has not been determined 
previous to the present instance as far as the writer is aware, and it is probable 
that there are other species which attack sugar-cane besides that dealt with in the 
present account. 

In 1936 there occurred at Blairmont Estate, Berbice, an outbreak of rats 
apparently unprecendented as far as actual records are concerned both as regards 
its proportions as well as duration and the damage inflicted, not only for that 
estate but also for any other in the Colony. 

About the same time there occurred on two other estates in Berbice, Pins. 
Rose Hall and Albion, outbreaks of the same species of rat. These outbreaks 
have not been dealt with in the present account as no special study was made of 
them, but from reports and information received and a couple of isolated visits to 
each estate it was evident that in a general way conditions on these plantations 
simulated those on Blairmont estate, although in neither instance was the out- 
break of the same magnitude as that of Blairmont estate. 

In this connection the writer has been informed by Mr. R. B. Hunter, Manager 
of Pin. Versailles, that about the year 1 889 a somewhat similar outbreak of rats 
occurred at Pin. Bath, Berbice, when sugar-cane was destroyed also. Mr. Hunter 
recollects especially that it was necessary on that occasion to replant a field as 
the result of the destruction of the tops by the rats, and also having seen the rots 
moving along one of the dams in numbers about dusk, apparently ooming into 
the estate from th% adjacent savannah. 



fei8 AdRiCUtTtfftAt SOXrf&kL Of BBlftafe GUUfcfA. tlX l 

The Outbreak. 

In November 1936, Mr. Q. M. Eccles, Manager of Bl&irmont Estate, consulted 
the writer in connection with the outbreak and investigations were commenced. 

The actual commencement of the outbreak Mr. Eccles informs me was in all 
probability about December 1935, when it was found in reaping a variety trial 
(field RP 24) that the plots of the seedling D 927/22 were completely destroyed 
by rats and had to be omitted from the results. In April 1936, the rate were 
first observed in large numbers in the cultivation, bat it was then considered to 
be a seasonal infestation which would soon pass. At the reaping in October 
1936 (Midlands 12-7) the seriousness of the attack was realized. It was then 
found that extensive damage had occurred and the yield in that section was 
seriously affected. 

When the new ratoon crop commenced to spring it also was attacked, and at 
the same time adjacent fields at a later stage of growth began to be attacked. 

For a while this condition continued, but later the damage appeared to cease, 
and for a few months little activity of the rats was observed. It was hoped, then, 
that the outbreak had terminated. In November ot the same year however, it 
was evident that the rats had become active again, and damage was fairly preva- 
lent in young fields. From that time to about the end of 1937 with only Blight 
interruptions the rats continued to damage the crop to a serious extent. 

By March 1938 the outbreak had apparently ceased and while rats were by 
no means absent they were not causing any serious damage. 

For the period November 1936 to December 1937 the total number of rats 
destroyed on Blairmont Estate was 127,449 made up of 25,543 caught after fields 
had been reaped either as the result of Hooding or in weeding and the changing 
of trash banks, and 101,996 caught by means of dogs at other times during the 
growth of the crop. At Pin. Bath between December 1936 and December 1937 
the figures were 53,157 and 33,869 and 19,288 respectively. 

Nature and Extent op Damage. 

As previously mentioned, the damage by the rats was first observed in canes 
at reaping. In these fields canes were found lying on the ground as the result 
of lower joints being gnawed by the rats, the cane subsequently breaking off and 
falling. 

In high cane examined by the writer in November 1936 this damage wag 
fairly prevalent. Although usually only a couple of joints were gnawed, at 
times as many as six or even more joints were destroyed in this way. Almost 
always such damage was confined to the lower parts of the stalks regardless of 
their height (Fig. 3). Occasionally however, a few joints higher up, and even 
as high as six feet from the ground were damaged. 

%n older canes sometimes the top of the cane was damaged. In such 
instances the central leaf and growing point of the stalk was eaten. Following 
this damage the stalk invariably commenced growth afresh from the buds lower 
down (Fig. 4). 8 



Plate XIV. 





Photo] 


i » 




I*. 0. Cioaro 

..... v a 




A WAtte feAf l>Att AGING StJGAR-CANB *» N&l'tlSH GUIANA. 210 


In young fields where the stalks were sot more than a couple of feet in 
height the damage took the form of gnawing of the shoots close to the ground. 
Shoots thus severed were not as a rule entirely eaten but were chewed and the 
juices sucked, the fibrous matter being discarded to a large extent. 

As to the extent of the damage some 1,500 acres on the Blairmont estate 
were involved, comprising principally of the sections Ram poor, Midlands, Olivier 
and Abary at Blairmont, Versailles and Locarno end to lesser extent Flanders, 
Old Bath and Diligence at Bath. 

The loss caused through the rats, like all field losses, is not easy to assess, 
bnt Mr. O. M. Eccles as early as November 1036 had estimated that in a single 
week’s working there had been a drop of “ 100 tons (of sngar) on the estimated 
yield from a block of first ratoons, entirely due to rat damage ” (in litt.). 

Estimating the loss due to the outbreak Mr. EccleB writes : — 

“ To assess the actual total damage is impossible. Apart from the direct loss 
“ from rat-eaten canes, we do know that we definitely had to throw out of culti- 
“ ration 225 acres, of which the spring was so badly attacked as to kill out the 
“ stools altogether, but for this these fields would undoubtedly have been carried 
“on as ratoonB for two or three years more according to ratoonage.” 

It was estimated that the loss in sugar on the Autumn crop of 1937 was in 
the vicinity of 1,200 tons. 


As to the loss in individual fields, or groups of fields, the yields of certain 
fields are given below, as plant canes and as 1st ratoons. 


Section. 

Field. 

Yield Plants. 

1st Ratoons. 

Ab 

1 

4.02 

2.22 


2 

3.90 

1.73 

Midlands 

3 

3.61 

1.43 

(10 acres) 

12-7 

5.66 

1 ’ 2.96 


The Rat. 

Specimens of the rat were submitted through the courtesy of Sir Guy 
Marshall, Director of the Imperial Institute of Entomology to Mr. T. C. S. Morri- 
son -Scott, of the Department of Zoology (Mammals Section) of the British 
Museum (Natural History) for determination. 

Mr. Morrison-Soott determined the rat as a new Bubspeoies of Hoplochilua 
sciurem which he called berbiccnsia, and a description was published by him in 
the Annala and Magazine of Natural Ilistory, Ser. 10. vol. XX, pp. 535-538, 
November 1937, in a paper entitled “ An apparently new form of Cricetine from 
British Guidha.” 




220 


AGRICULTURAL JOURNAL olf BRITISS GUIANA faX 

The following are the measurements and description as given (loo. dt.). 


] u 


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i 55 “ 

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body 

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2 



A WATER RAT DAMAGING SUGAR-CAlfaS IN BRITISH GUIANA. 221 


“ Deaoription — Head and body dorsally a blackish olivaceous brown due to 
“a mixture of yellowish buffy-brown hairs and black hairs, black predominating. 
“ Flanks clearing to cinnamon-buff. Arms and legs like flanks. Ventrally 
“smoke-grey, washed with yellowish cinnamon, strongly so on middle of belly. 
"Hands same as back. Hind feet greyish bnff. Tail grey. 

“All from same locality and caught in same month. Skin-measurements by 
collector in flesh.” 

Mr. MorrisOn-Scott compared the specimens with 27. guianac Thomas 
(Ann. and Mag. Nat. Hist. (7) VIII, p. 149, 190) and gives the following 
characters : 


27. sc iu reus berbicensis. 

1. Strong admixture of black 
hairs dorsally 

2. No rusty tinge on back 

3. Tail grey 


27. guianac 

1. No black hairs dorsally, dark 
brown at most 

2. Rusty tinge on back 

3. Tail reddish-brown. 


The type locality of II. guianac Thomas, is Kanaku Mts., British Guiana. 

Finally, Mr. Morrison- Soott concludes : “ It looks as though sciureus is not 
“confined to the Amazon drainage area but extends into the savannahs of 
“ British Guiana, and that berbicensis is just a coastal form. ” 

Since the publication of Mr. Morrison-Scott’s paper further specimens have 
been submitted to him. 


Of two specimens from Pin. Versailles, West Bank Deinerara, Mr. Morrison- 
Scott says (in litt.) : 

"Nos. 1' 9 and 19. These are Without doubt berbicensis. True they are larger 
“than the type. [The length of head and body were 210 mm. and 200 mm. 
“respectively— L.D.C.] ... A fairly reliable index is to be found in the teeth 
“which do not alter much and No. 18 has the maxillary tooth row exactly the 
“same length as the type and No. 19 has this row 0. 15 mm. sihaller. The 
“condylo-basal lengths are No. 18—38.00 mm. and No. 19 — 38.95 mm. ” 

As regards two other specimens which had been in captivity for some 
seven months and in which a reddish coloration had developed a couple of weeks 
before they were killed, Mr. Morrison Scott says— 

4 

“ Nos. 21 and 22 are exceedingly interesting. They approximate very 
“closely to the type of guianac but their tails are not reddiBh-brown enough 
“(the root of 21’s tail is about the right colour). I do not think the red is 
“seasonal because they were killed at the same time as 18 and 19. I wonder if it 
"is some condition of captivity ? The patch of red on 22’s head seems abnormal. 
“I should be extremely interested to hear if you get any wild reddish forms— 
'* guianac (= Sciureus) may of course overlap with berbicensis. ” 



AGRtCTTLTtmAL JOtfRSAt 6F BRITISH GTTtASA. 


t!t, 4. 


222 

The male of I berbicensis is both larger and heavier than the female. Meas- 
urements have been given already. The average weight of 12 males was 167.1 
grammes with a minimum of 111 gms. and a maximum of 220 gms., while the 
average of 10 females was 96.7 gms., with a minimum of 61 and maximum of 
133 gms. 

Ecology. 

Habitat .-—At the rear of Blairinont Estate and the adjoining Pin. Bath and 
separated from the actual sugar-cane fields by only the empoldering dam and its 
canal is a vast savannah. During the wet season this savannah becomes Hooded, 
to a depth of about eighteen inches to two feet of water. 

The vegetation of this savannah is principally the sedge known as “ Bizzi- 
bizzi” ( Gypcrns articulate L ). Interspersed amongst this, in old water courses 
which are known as “creek hands”, grows the broad-leaf bamboo-grass or 
Missouri grass as it is sometimes called, Hi/mcnmhm * aniplexiraulis (Rudge Nees). 
There is also in places areas of Hrluotua, probably H. psitlicoruin L. while on 
fringes which abut the dams of the estates is also Panu um luxum Swartz. 

f 

The outstanding feature of the area as far as the outbreak of rats was 
concerned was the areas of bamboo grass This grass which forms rather thick 
clumps appears to offer conditions suitable to the rat for breeding and it is 
believed that this is their natural habitat. 

When the investigation commenced it soon became apparent that the fields 
principally attacked were those situated adjacent to the savannah aiea. For 
instance, the attacks in May 193(5 occurred in M. 7/12 section, and it was not 
until the following year that the rats had penetrated to M. 1/6. 

Similarly, when the writer first visited the estate in this connection it was 
the Abary sections that were suffering from attacks of the rats. 

Later it was found that similar conditions as to proximity of attacked fields 
to savannah held good at Pin. Bath also, for although the rats appeared in the 
sections Old Bath and Diligence on that estate which are situated at the front of 
the estate these sections have savannah areas in their rears, 

A careful examination in the Abary fields at Blairmont when they were 
first visited revealed “spoor” of the rats which indicated that the animals were 
crossing the dam and trench separating the section from the savannah. Farther, 
most of the damage ocourred at the savannah ends of these fields. 

All the field conditions, therefore, pointed to the rats having invaded the 
cultivation from the adjoining savannah. This was farther confirmed by the 
statements made by East Indian labourers who had crossed these savannahs to 
the effect that large numbers of rats which had been drowned were seen in the 
savannahs and that in places where the land was either higher or in little 
hammocks, many rats colleoted. 



A WATER BAT DAMAGING SUGAR-CANE III BRITISH GUIANA. 223 

Food and feeding habits- — la their attacks on sugar-cane the rats fed beth on 
the young eane-shoote as well as on hard cane, and even on the “tops'’ of tall 
oanes, according to the growth of the fields. 

When yonng fields are attacked the shoots are entirely severed and portions 
of the softer white tissue at the base are consumed, the major part of the shoot 
being left uneaten on the ground with finely gnawed tissue. 

In the older fields where joints hare been formed these are gnawed, in most 
instances the joint nob being entirely severed, but the stalks often break as the 
result of bhis damage so allowing farther gnawing along the length. In this way 
the same stalk may be eaten over a period of several days and a number of 
consecutive joints destroyed, extending sometimes for a length of more than two 
feet of stalk. 

While all varieties of cane were attacked there was a preference which was 
quite marked — thus Diamond 10 appeared to be preferred to D. 625, while other 
preferred varieties were Co 213, D 927/22 and D 74/30. Thi3 variety preference 
was so marked that in different trials the seedlings D 927/22 and D 74/30 were 
damaged to such an extent as to prevent suitable samples being obtained for the 
purpose of the experiment. 

The natural food of the rat there can he little doubt is the stalks and seeds of 
grasses in the savannahs, and the stalks of bamboo grass are often quite as 
succulent as those of young sugar-cane. Instances have been observed also 
where the rats fed on the stalks in clumps of razor-grass ( Paspalum virgaium L.) 
on dams situated between the savannahs and fields. This grass is, however, not 
an inhabitant of the wet savannahs which are the natural habitat of the rat. 

In laboratory rearing the rats were kept for many months feeding readily on 
on young cane-shoots, shoots of guinea grass (Pan i cum maximun Jacq.) and also 
on padi. 

In feeding, after the shoot has been gnawed the rat takes a portion in its 
hands, then sitting more or less upright proceeds'to eat it using its hands to hold 
the food. When feeding on padi the grain was held to the mouth in the same 
manner while the outer shell was removed, the grain being then consumed and 
the husk discarded. 

Iu the laboratory a fair amount of water was taken also. 

In the field, feeding appears to be entirely nocturnal, or at least at dusk and 
again also in the early morning hours. This was so in the laboratory also, at 
least at the beginning, but after rats had been in confinement for some time 
they would commence to feed when supplied ‘ with fresh food about 4 p.m. 
although they were never observed to feed earlier than this or later than about 
9 a.m., except under stress of hunger. 

The amount of food consumed has been determined as regards padi as this 
was a convenient material to work with. For one lot of 28 rats over a total 



224 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4 . 

period of 574 rat-days, the average consumption of padi per day was 11.2 
grammes per rat, while for another lot of 21 rats over a total period of 113 rat- 
days, the average consumption of padi was 9.7 grammes per rat. 

Conditions conducive to outbreaks . — As to the conditions which bronght 
about the ontbreak we can form an opinion only in so far as the conditions 
observed some months after the rats had become prevalent will allow. 

That the rats came from the savannahs in rear of the estates there is no 
doubt, and likewise there can be no doubt that these savannahs are their 
natural habitat. 

Whether severe and excessive floodings of the lands, or an over-population 
of the area was the primary cause of a migration of the rodents to the adjacent 
cane-lands, it is not possible to say. The fact remains that snch migration did 
occur and that the savannahs, at least in November 1936, were flooded to an 
abnormal height. When the rains subsided later the catches of rats diminished, 
but again increased some months after when the next wet season occurred, and 
kept up as the numbers of rats show, to some extent during 1938 which was a 
particularly wet year. ' 

The number of rats caught in the different sections, with total and the 
number per acre, show that it was the sections adjacent to the savannahs which 
in the beginning were moat severely attacked, both at Blairmont and at Bath, 
the intensity diminishing and the attacks taking place later as they extended 
away from the savannah. Later, however, as the rats spread through the areas 
some of the most severely attacked fields were situated at some distance from 
the savannahs. 

As the outbreak continued there was a gradual advancement of the rats into 
the longer established areas of cane, and there can be little doubt that this 
species of rat will become, if it is not already so, a permanent resident of the 
cane-fields. The rats from Pin. Versailles (Nos. 18 & 19) were taken under 
ordinary conditions in cane-fields, and it would seem that in this area at least the 
permanent association with cane-fields has already occurred. 

It has been suggested that the rats were attracted to the cane and to attack- 
ing it by some condition and change in its composition, imperceptible to 
ourselves, brought about by waterlogged conditions of soil which are associated 
with newly-empoldered savannah lands, and that this was the primary cause 
of the outbreak and farther, that as such lands became “ better drained ” the 
outbreak would automatically cease. 

It is impossible with our present knowledge to prove that such is not the 
case, end the fact that later the outbreak ceased would seem on the face of it to 
substantiate this. It is true also that in newly-empoldered fields water-logging 
dags occur at times, and that in some of the fields at Blairmont estate there were 
indications of such being the case, and that in such fields rats did cause consider- 
able damage. This was not by any means general of the fields attacked, however, 
and certainly was definitely not so of certain fields which the writer observed in 



A WATER RAT DAMAGING SUGAR-CANE IN BRITISH GUIANA. 


225 


November 1936, where young canes were being severely damaged by the rats. 
Against that, too, we have the fact that the outbreak although originating on the 
recently empoldered lands was not confined to it, indeed, as far as Blairmont and 
Bath were oonoerned, aotually was as severe on some sections which had been 
empoldered years previously as on those only quite recently taken in. In addition 
of course, we have the taking of the rats at Pin. Versailles in fields of long stand- 
ing. 


With the older established fields, even when these are adjacent to savannahs, 
it appears that razor-grass (Puspalum virgatum L.) on dams plays an important 
part in serving as an intermediate in the spread of the rats to the cane-fields. 
After an area has been taken in, razor-grass soon establishes itself on the dams 
and at times forms a very definite and extensive association in such places, some- 
times almost to the exclusion of the other grasses which were previously growing 
there, and while it does not ever completely take over the dams it may become 
the dominant species (Fig. 2). 

Under such conditions the dense clumps of this grass have been observed to 
act not only as cover, but to serve also as nesting places for rodents, and it is 
believed that it may thus form a nidus for the rats. 

Although it has been stated that the number of rats caught per week shows 
some correlation to the rainfall this should not be interpreted too literally and the 
prevalence of the rats considered entirely as seasonal. Consideration must be 
taken also of the fact that when these rats invade cane-fields they live in the 
interstices of the soil, made in the course of its cultivation with an agricultural 
fork, and with the advent of heavy rains they are driven from such places and 
are then more easily caught by dogs and labourers. These rats have not been 
observed to make burrows, but this may be due to the large amount of cover 
offered as the result of the method of cultivation as mentioned. 

Natural Enemies . — The principal enemy of Hoplochilus observed in the 
outbreak was an Oestrid larva. Although not abundant it was of frequent occur- 
rence and accounted for a fair number of rats, not perhaps directly in itself, 
although the injury inflicted in this way was sufficiently important, but more 
usually through the septic condition which followed as a result of its attack, 
and the secondary infection of Cochlyomyia that often followed in its wake. 

The Oestrid larvae were usually situated behind the arms of the rat but 
sometimes also a little further along the body in the vicinity of the ribs. While 
usually only a single larva was found on a rat, sometimes as many as three would 
occur in one host. 

The fly concerned has been determined as Cutebra apicalis Guer. by 
Dr. Van Emden through the Imperial Institute of Entomology, London. 

A mite also was found frequently on these rats but this is of no economic 
importance, # 



226 AGRICULTURAL JOURNAL Of BRITISH GUIANA. ftOK* 4 

While we have no proof that these rats are attacked by ssu^ee, 
conditions observed point to this. On the empolderiug dam between the 
savannah and the newly taken in fields, the water snakes Liophia cobella Linn, and 
Helicops angulata Linn, were prevalent, and in the olnmps of razor-grass ia 
which the nests of rats were frequently found, egg-masses of these snakes were 
of frequent occurrence. 

During the rat outbreak there was a marked increase in the number of 
snakes also, bnt they diminished with the lessening of the number of rats. 

Control Methods. 

Hunting .— The first efforts at control directed against the rats was hunting 
with dogs, and this continued throughout the campaign. This is the method 
adopted on sugar estafaas as routine against the normal rat population of the cane- 
fields, and it is bnt natural that it should be extended when conditions became 
more acute. As to its value as a means of control in epidemics of the nature of 
the one here described it is open to much discussion. 

f 

Still with a pest attacking large areas of crop and causing losses of the 
extent shown above, it is only reasonable to adopt snch measures as appear 
effective on the face of them. 

The actual figures of numbers of rats caught as given below do not show 
that the catching of large numbers of the rodents had any immediate or percepti- 
ble results, and one is left to conjecture whether there wonld have been any 
material difference in the position for the worse were such measnres not 
undertaken. 

The method of hunting consisted merely of men going through the cane- 
fields, and over the newly empoldered lands, with more or less trained dogs 
which located the rats and drove them from their hiding places. The rate were 
then seized by the dogs and killed, bat were secured by the men before the dogs 
conld devour them as payment was by results on the number of rats secured. 
The dogs nsed for this purpose comprised a miscellaneous collection of mongrels 
of particularly lean and halfstarved appearance generally grouped under the 
non-committal term of “hunting dog”, which, nevertheless, were very efficient at 
the work (Figs. 5 and C). 



Plate XVI. 



[L. D. Cleare. 


x auiuj ^ 

Fk. 5 — Ratcatchers with clogs w orkmg over savannah recently empoldered and ploughed. 



Photol (L D. Cleare. 

Fig. 6. — Ratcatchers with their “ hunting dogs ” working in taller canes. 






i Wat'hr sat? Damaging stfGAR-cAini is iaWifitf gWaSa. 22? 


The number of rats caught on both Blairxnont and Bath estates are given 
below month by month for the period November 1936 to October 1938. 



Blairmont Estate 

Bath Estate 

Total 

1936 




November ... 

1,153 


1,153 

December ... 

36,047 

2,008 

38,655 

1937 




January 

23,202 

7,942 

31,204 

February 

9,044 

11,746 

20,790 

March 

7,200 

7,798 

15,058 

April 

5,741 

11,574 

17,315 

May 

10,0<S7 

4,296 

14,983 

June 

8,247 

1,790 

10,037 

July 

4,589 

913 

5,502 

August 

5,302 

1,245 

0,547 

September ... 

3,654 

255 

3,909 

October 

1 3,485 

1 330 

3,821 

November ... ..J 

1 3,698 

788 

4,480 

December ... 

4,680 

2,460 

7,146 

VXib 




January 

8,081 

860 1 

8,947 

February 

1,894 

1,051 

3,545 

March 

1,202 

2,582 

3,784 

April 

2,811 

3,118 ' 

5,929 

May 

4,139 

1,421 , 

5,560 

June 

930 

42 ' 

972 

July 

1,847 

223 I 

2,070 

August ... ...' 

4,597 

087 1 

5,284 

September ... 

1,935 

144 

2,079 

October 

66 

M I 

84 

Total 

154,951 

03,909 1 

218,860 


Poison Baits,-— Within recent years there has grown a considerable literature 
On rat control, and papers on this subject have been published in many parts of 
the world. In many instances the publications have been concerned with the 
common house rats (Mus) although some deal with field rats and even species 
attacking sugar-cane. In most of these publications poison baits artfrecommend- 
ed consisting principally of red squills, barium carbonate or white arsenic, and 
more recently thallium sulphate has come into considerable favour, in 
Combination wjjh substances considered to be attractants. 



AGRlCULftttUL JfOUMAt OS' SRttlSH QtflAUA, tlX, 4. 

So when hunting with doge did not appear to rednee materially the numbers 
of rats and other methods were sought, this was the line of attack which was 
taken. Phosphorus baits were first tried in the old West Indian form of “sulphur” 
matches stuck into bananas, which at the time was giving good results in 
Trinidad against rats in cacao-fields. Here the bait was not successful ; the rats 
soon learnt to recognise it and either did not take the bait, or removed the 
matches and consumed the portion of the fruit which was not affected I 

Other baits then received attention. Stock formulae recommended and uBed 
elsewhere with barium carbonate and white arsenic as their bases were tried, 
and later substances other than those usually recommended as attractants were 
used with the hope of increasing their efficiency. In this way most of the easily 
obtainable food substances were used including bananas (ripe and green) bread, 
butter, cheese, fish (salted cod), Hour, lard, oats, (grain and meal), oil, cotton- 
seed), padi, potatoes (English and sweet), maize (grain and meal), and 
saocharine. Sometimes in addition aniseed oil very diluted was added as an 
additional attractant. Later several proprietary rat poisons received attention as 
well as rsrt virus. 

At the outset it must be stated that, all of the substances mentioned 
previously, and all of the proprietary rat poisons, were taken by the rats to a 
greater or lesser extent, and when fed to laboratory ruts sooner or later proved 
fatal, with the exception of rat virus, which probably had deteriorated in 
transit. In spke of this it was evident that none could be considered as being 
likely to prove a successful means of control for these particular rats. 

The most successful of these baits proved to be padi upon which was 
sprinkled a proprietary rat poison of which arsenic trioxido was the active 
constituent. A variation of this which provod to be highly toxic was padi 
sprinkled with Paris green. 

In the padi-arsenical trials it was revealed that the rata in feeding on the 
padi removed the husks and ate principally the grain within. It was evident 
then that any poison to be used should penetrate into the grain. Sodium 
arsenite in aqueous solution of 4 per cent, was therefore tried. Padi was 
soaked in this solution for 24 hours, then removed and allowed to dry by air. 

In laboratory trials the bait was taken freely at first Mid proved extremely 
toxic, as little as 1 gram of treated padi (about 15 grains) being a fatal feed. 
In the field, too, where the bait was set ont in “torpedoes,” (t.c., in a Wow’ of 
protecting paper) it was readily taken at first, and no donbt was equally effective. 
As with other baits the rats soon became “wise” to the presence of the poison 
and then did not take it readily. In fact in the laboratory after a time, even 
under the stress of no alternative food for several days, the rats refused to feed 
upon padi so treated, bat when untreated padi was substituted they fed 
immediately and extensively. 

% Thallium sulphate baits, made to the usual formula bnt with padi in place of 
wheat at the rate of 1 to 500, pat up in “ torpedoes” was readily taken and the 
rats did not appear to detect the presence of this substance. .With this bait it 



a Water rat damaging sugar-cane in British guiana. 229 

ml evident that the amount of thallium would have to be increased if the bait 
was to be effective. About this time (March 1938) the numbers of rats caught 
began to decrease, damaged canes seemed less in the fields, and trials with baits 
were discontinued. 

In placing baits in the fields, especially during periods of heavy rains, it 
was found that “torpedoes" did not offer an efficient protection and as a result 
the baits deteriorated rapidly, farther, the “torpedoes" were sometimes punctured 
by ants. The best results were obtained by setting out the baits in galvanised 
iron pans, or enamel-ware plates about 10 inches in diameter under roof -shaped 
galvanised covers of a sufficient size to afford complete protection, with the 
openings directed away from the prevailing wind. Although baiting in this way 
is not as easily done as with “torpedoes" no difficulty was experienced as 
the covers and pans are both light and easily porbable, and the protection offered 
more than offsets this. 

The indications from these trials of poison baits was that arsenicals, 
especially sodium arsenite in aqaeous solution absorbed by the padi, and 
thallium sulphate, are both useful poisons for these rats, particularly the former 
on account of its inexponsivenesc. 

Further work would need to bo carried out in connection with sodumi 
arsenite on the minium fatal dose and also the finding of some means of making 
the padi more attractive and/or disguising the presence of the poison in baits, 
should this be necessary when less poisonous amounts are used. 

As for the situation at the present time, Mr. Eccles writes, “ while the 
“ punt-loaders still seem to catch a fair number of rats, there are practically no 
“signs of damage either when one rides around the cultivation or goes into the 
“ fields. In fact, had it not been for our past experience, we should certainly 
“ not be bothering to catch and pay for rats now, as we should have said we 
“ ‘ hadn't got any ! ’ ” 

Summ \RY. 

An account is given of an outbreak of rats which occurred at Rlairmont 
Estate, Berbice. The species of rat concerned was found to be a new subspecies, 
namely Hoplochilu s sciuieus bcrbicensm Morrison-Seott. 

Similar outbreaks occurred on other estates in Berbice about the same time, 
although these were not of the same magnitude. 

The ecology of the outbreak is dealt with, and some account is given of the 
means adopted for dealing with it. 

Acknowledgments. 

In preparing this account the writer is very conscious of the extent to which 
he is indebted to Mr. Q. M. Eccles, Manager of the Blairmont Estate. The 
situation of the estate at Borne distance from headquarters and the pressure of 
other work prevented frequent visits being made, and as the result much of the 
routine work and the trials with poison baits was oarried out under the super- 
vision of Mr. Eccles, who, moreover, deputed Mr. L. R. Barker, formerly 
Deputy Manager, and Mr. J. A. By water to assist with the work. 



A S&ORT HISTORY OF THE RUPUNUNI SAVANNAHS 
WITH SPECIAL REFERENCE TO THE LIVESTOCK ‘ 

INDUSTRY. 

BY 

H. E. TURNER, 

General Manager , ltupununi Development Co. Ltd. 


Civilization came to British Guiana mainly through the medium of the 
Dutch. They occupied the coastal lands and such alluvial belts as lay along the 
various rivers within tidal influence. Sugar, Cotton, Coffee, Cacao, etc., were 
grown for export, and labour in the form of slaves from the West Coast of Africa 
was supplemented by the enslavement of Aboriginal Indians, stronger tribes often 
capturing and trading their weaker neighbours. As the supply of Aboriginal 
Indians became exhausted close at hand, expeditions were led higher up the 
rivers and military posts erected at strategic points. A small military post was 
built at the confluence of the Rupununi and Essequibo Rivers, and eventually 
the open country to the south, which is an offshoot of large savannahs of the 
Rio Branco, was discovered. No attempt was made by the Dutch to settle the 
savannahs of the Rupununi. 

At the same time, civilization was proceeding along the Amazon through 
the medium of the Portuguese, who discovered the large savannahs of the Rio 
Branco, and used them as a dumping ground for all criminals under long sentence 
Of imprisonment. To assist these deported prisoners, the Government sent up a 
small number of cattle, and it is from this nucleus that have sprung the large 
herds that have formed practically the sole support for an ever-increasing popu- 
lation in the Rio Branco District of Brazil and the smaller savannahs of the 
Rupununi District. 

Towards the middle of the last century, British and Brazilian interests met 
horth of the Kanaku Mountains midway between the Rupununi River and the 
Takutu and Ireng Rivers. British missionary met Brazilian rancher near the 
site of the mythical lake Amaku, on the shores of which the early adventurers had 
boped to find the golden city of Manao. A clash ensued; each side was backed 
by its respective government, and armed forces were dispatched and faced each 
other near the Macusie Indian Village of Pirara, where a mission had been 
established. Eventually both sides withdrew and in 1906 the disputed area 
was finally awarded by arbitration to British Guiana. 

Riohard Schomburgk in his “ Travels ” gives a highly coloured picture of 
Conditions at Pirara when he first visited there in 1842 in company with the 
British armed expedition. His account of Brazilian ranching activities should 
be taken with the proverbial ‘grain of salt*, At the time, it is doubtful if there 



A SHORT HISTORY OF TH8 RTTPUJTOKI SAVANNAHS, 831 

was a single ranch or outstation established on what is now British territory. 
Stray cattle no donbt had crossed the Takntn and increased in the nnoccupied 
country towards the Rupunnni. Schomburgk speaks of rich pastnres, large herds 
of cattle, galloping vaqueroa, etc., but what he in all probability witnessed 
was the annual round-up of a few hundred head of stray cattle. 

The Rupunnni Savannahs are divided into two almost equal parts by 
the Kanaku Mountains which run from east to west to within three miles of 
the Brazilian border. At this period, the southern half, now held by the Rupu- 
nnni Development Co., Ltd., was entirely in the hands of the Aboriginal Indians, 
without encroachment by either British or Brazilian. Slave raiding by the 
Brazilians seems to have been prevalent and Schomburgk describes raided and 
bnrnt Macusie Villages in the Eanaku Mountains. Inter-tribal warfare also, no 
doubt for the purpose of taking slaves, still went on, and many years ago the 
writer heard the then oldest member of the Wapisiana tribe describe how he 
was taken as a small boy to see the site of the last big fight and found discarded 
weapons still scattered about. 

Latterly, however, the remaining Indians were left in peace, and by the 
middle of the last oentury were in sole possession of the savannahs with appar- 
ently little or no external influence affocting their mode of life, habits or 
economic outlook. A few white men toured the llupununi from time to time in 
search of minerals or in scientific exploration, but the long, slow and costly 
transport of that day presented too many difficulties to encourage permanent 
settlement. 

Some time between 1860 and 1870 a Dutch trader named De Roy and his 
wife settled on the upper Rupunnni, near to what is now Dada-nawa. Ham- 
mocks and other articles of aboriginal handicraft, together with local birds and 
animals, which the natives are adept at rearing as pets, were purchased in 
exchange for salt, knives, fish hooks, etc., and disposed of on the coast. De Roy 
also introduced cattle into this part of the Rupunnni by the purchase of some 
three or four head from Brazil for milking purposes. 

Twenty years after De Roy’s arrival, Melville, who played a great part in 
the development of the District, penetrated to the Upper Rupunnni in search of 
gold. Finding the life of a trader more congenial, he settled in the District and 
also purchased a few head of cattle from Brazil, together with several horses. 

De Roy and his wife died towards the close of the last century and Melville 
bought up' his entire estate, including one hundred and twenty head of cattle, 
the increase from the original three or four. Including these, Melville’s total 
purchases of cattle mounted to some three hundred head, and the majority of 
the cattle now in the Rupunnni come from this one small herd of &rub stock, 
with little or no introduction of fresh or improved blood. 

Melville was a man of extraordinary personality and energy, but he had 
been bred a townsman and had only very elementary knowledge of aniiR$l 



232 AGBIOtLTtJBAt. JOUBBAt OF BRITISH GHUHA, [IX, 4. 

husbandry. The result was that h« left the care of his cattle under the supervi- 
sion of a few Aboriginal Indians, who had learned a little of the local methods 
of handling stock in Brazil, where ranching, although conducted on very crude 
lines, was becoming an industry of some importance. As in every country 
blessed with natural feed, an ample rainfall and a complete freedom from 
disease, Melville’s cattle throve without care and increased at a rapid rate. 

There being no overland communication with the coast, all trade was with 
Brazil. Manaos was fast becoming an important entrepot and port for the robber 
and Brazil nut trade of the Amazon, and at the beginning of the century, Melville 
was exporting a few steors there, through the medium of Brazilian friends. His 
cattle roamed the range entirely without care, except for an annual round-up for 
branding, and as they increased and spread further afield, even this was omitted. 
No castrations were done under five years of ago : hence there could be little 
selection of bulls. In-breeding was rampant) and progressive, and the methods 
of handling crude in the extreme. Cattle were becoming extremely wild and 
difficult to round up, in fact only those in close proximity to Melville’s residence 
at Dada-nawa were under control. These methods were continued np to, and 
even after, the time when Melville was able to sell out to a company, and even 
with the advent of fresh settlers, economic conditions have militated against any 
great improvement on these original methods of stock management. 

The standard coin of Brazil is the milreis which in the early j ears of the 
present century had an exehange value of approximately one shilling. The steers 
from the Rupnnnni had a splendid reputation for size and quality, directly 
attributable to the fact that the country was still understocked. Standard steers 
were freely bought on the spot by Brazilian buyers for one hnndred milreis 
(five pounds) and selected steers would run to one hundred and fifty milreis. 

Export of steers from the Rupnnnni to Manaos was always difficult. The 
state laws forbade it and everything depended on the activity or cupidity of the 
particular officials in office. Sales becoming increasingly difficult, Melville 
approached the Government of British Gniana in 1917 with the project of cutting 
a trail to connect the savannahs with the steamer terminus on the Berbice River. 

The proposal was a timely one, as the course of the Great War, which had 
been in progress some three years, was responsible for inflated prices and a food 
shortage, and the project was approved by Government. The construction of 
the trail was placed in Melville’s hands, and towards the end of the year 1919 a 
few selected tame animals were driven to the coast and the trail declared open. 

As a result of this, the Rupnnuni Development Co., Ltd. was floated, 
acquired Melville’s cattle interests in the Rnpununi, and bought out two of the 
four small Brazilian ranchers who had been allowed to settle on the British side 
of the border. In addition, a few individual settlers started ranching. 

Wien, however, attempts were made to drive down herds of the ordinary 
wild range cattle, it was found that the trail was a cattle trail in name only, and 
lacked every facility for the driving of Btock. Actually, the trail r at this period 



Plate XVII. 



Fia. 2— Crossbred Zebu Hereford Heifei (J Zobu, j Hereford, 1 Rupununi) 






Plate XVIII. 



Fic. 4 — Driving a Mixed Herd 







A SHORT BISTORT OF THE RUPTTITOIW SAVANNAHS. 


233 


was nothing more than a clearing out through the forest with all trees over four 
inches in diameter loft standing. Clearings for grazing, and paddocks or corrals 
for holding the cattle at night, were non-existent. High creek banks weie un- 
graded, and the swamps, lacking corduroys, were well-nigh impassable. Rest 
houses there were none, and the trail proved a ‘via dolorosa’ for both man and 
beast, so that for the first two years the losses incurred in driving cattle through 
it were terrible. 

The Rupununi Development Co., Ltd. now owns the larger part of the stock 
in the Rupununi and therefore a short account of its development will not be 
out of place. Towards the end of the Great War and in the early post-war years 
a wave of speculation swept the Colony. Sugar— the staple industry — was 
booming, and it was only natural that the opening up of what was considered to be 
a rich and undeveloped stock-raising country should be expected to result in 
added prosperity. 

Floated towards the ond of llUH, the properties acquired by the Rupununi 
Development Co., Ltd. were purchased at a figure far above their actual value. 
The main property , Dada-nawa, was a ranch in name only. Equipment, fences, 
corrals, etc., were non-existent. Thero were some 15,000 head of scrub cattle of 
which a few only could be termed domesticated, the remainder being 
little better than wild animals. Despite the fact that there was talk of raising 
cattle by the hundreds of thousands, overstocking was already in evidence in 
some places (though large areas of course were still entirely unstocked) and 
numbers of cattle were of poor conformation, stunted and in wretched condition. 
Little notice had as yet been taken of the warning of Professor Ilarriaon, 
Director ol Science and Agriculture, that nving to the lack of essential minerals 
and the sterility of much of the soil, the number of cattle that the savannahs 
could support was limited. IIo estimated one animal to twenty acres, although 
an overall average of one to thirty acres iv ould now be nearer the mark. 

Amply provided with working capital, the policy should have been to devote 
the first year at least to organizing and equipping th<‘ ranches, and perfecting 
a system of driving the herds through the newly opened and as yet untested 
trail. Unfortunately, owing to lack of knowledge of conditions up-country 
an exactly opposite policy was adopted. Hords of cattle were, without prepara- 
tion or organization, rushed away from the ranches, the majority to be lost in 
the roughly cut cattle trail. But the post-war slump bad already set in, live- 
stock values were dropping and all other activities were neglected in an 
attempt to bring large numbers of cattle to the coast. 

By jho latter part of 1921 the Company’s position already seemed hopeless. 
Almost the entire working capital had disappeared and but few steers had 
arrived on the coast tor sale. Nothing had as yet been done towards the 
development of the ranches. Actually, they were in the same condition as when 
pnrohased, except that the best of the steers had already been removed, the 
majority to be lost in transit to the coast. A reorganization was obviously 
essential and this was carried out, the Company narrowly avoiding liquidation 
and being lefbfinancially crippled. 



234 AGRICULTURAL JOURNAL OF BRITISH GUIANA, [IX, 4 , 

The second phase consisted of a long nphill struggle without reserves and 
against a constant drop in livestock prices which continued until 1936. During 
this period, everything possible was done to develop the ranches, but economic 
conditions limited the progress made. Pure bred bulls were imported, scores 
of miles of fencing constructed, numerous out-stations built and tho cattle brought 
under control. Improvements could only be carried out when livestock prices 
allowed of a working profit being made, and during this second phase all such 
profits were put back into the properties. Progress has, however, been slow and 
the quality of the stook still leaves much to be desired. 

So much for the Company. The history of the small settler has been 
even more unfortunate, and those not possessing some alternative source of 
revenue, such as balata bleeding, were in many cases reduced to a state of dire 
poverty. At one period, ranchers were driving their cattle to the coast to sell 
for $10 per head and of this amount $1.50 was paid for trail toll and over $3 
in freight from the terminus of the trail to Georgetown. It was felt by them 
that although for years the cry had been to settle the interior, and the Rupununi 
District was the only part of the far interior where settlers, the majority 
Europeans, lived, worked and brought up their families, yet their pioneering 
problems were either completely ignored or treated with scant sympathy. In 
an area of several thousand square miles with a resident population of at least 
four thousand there is still no medical service and only one small mission 
school for Aboriginal Indian children. 

Under these conditions, the small rancher has done little or nothing 
towards improving his stock. For some considerable period in fact he entirely 
discontinued driving his cattle to the coast, as the price obtained barely covered 
the expensos incurred between ranch and market. 

The main reason for his economic troubles, apart from the difficulties of 
communication, is the poor quality of his stock. He in caught in a vicious 
circle, since his poor quality cattle bring low prices, and these allow of no 
surplus to be expended on the improvement of stock. lie has been blamed for 
being unprogresbive, but the fault is not entirely his. It is possible that if 
Government, when opening tho cattle trail, had started a small stock farm in 
the District for the purpose of breeding improved beef type bulls for sale to 
the settlers, there would now he a different tale to tell. Settlers who were in 
no position financially to import their own pure bred bulls into the District 
would undoubtedly have purchased cross breds on the spot had they been 
available. 

In the early days, stock in tho Rupununi was entirely free from disease, but 
the same cannot be said to-day. A veterinary surgeon permanently stationed in 
the District is needed, or failing this, a lengthy visit by a properly equipped 
veterinary expedition definitely to establish tho naturo of the stock diseases 
now prevalent in the District, and advise settlers on the methods of combating 
them, 



A SHORT HISTORY OF THE RUPTJHTJNI SAYAJWAHS, 


235 


The idea that the Rupununi District is a rich stock-raising area capable of 
holding hundreds of thousands of head of cattle is a fallacy. Although certain 
areas are still capable of holding more cattle, large areas are already heavily 
overstocked, and this mainly accounts for the extremely poor quality of much 
of the stook. 

The soil of the Rupununi savannahs consists of two main types. In the 
first place, there is the sandy soil of the high lands and low hills and ridges, 
which Professor Harrison described as being 4 barren to sterile*, and it has 
been proved that the coarse tuft grass growing on these areas is markedly 
deficient in minerals and of practically no feed value. Cattle will only graze 
this grass whon it is springing up soft and green after burning, or when forced 
to by lack of pasturage on the low ground. 

Secondly, thero is the clay soil of the flats and low ground which mostly 
lies along the creeks and rivers. These flats flood over for short periods during 
the wet season and receive deposits of alluvium. Much of this soil is of well 
marked fertility, and although deficient in essential minerals , produces herbage 
of definite nutritive value on which cattle thrive . It may here be noted that 
the feeding of artificials to the stock to make up for tho marked mineral 
deficiency in all types of grazing is, under present conditions, almost out of the 
question owing to the extremely high cost of transportation from the coast. 

For all practical purposes, therefore, the grazing on the high lands can be 
regarded as of little or no value. This means that the number of cattle that 
can bo carried on any given area is limited by the extent of tho low lands. 
Certain areas are almost totally deficient of good pasturage, and it is tho absence 
of cattle in these areas that gives rise to the reports that the savannahs are still 
very much understocked. 

Taken as a whole, the grazing which is of value does not comprise a fifth of 
the entire area. When a range is xmderstocked, the cattle graze in the most 
favourable swamps only, and as a rule are in splendid condition. Once tho 
economic stocking-up point in numbers is passed, however, these good grazing 
areas become denuded of grass, and eventually semi-starvation forces the cattle 
to graze on the coarse grass of the high lands. When this occurs, the stock be- 
comes miserable in tho extreme both as regards size, conformation and condition. 

To, sum up, tho Rupununi savannahs in the writer’s opinion can produce 
some five thousand head of marketable steers per annum together with a 
proportionate number of spayed females. Owing to the sparseness of the 
grazing, the open range system is the only economic method of running the 
main herds, but fencing is essential for tho purpose of breeding vfp small herds 
of improved stock to provide bulls for the open range. Adequate fencing, 
better bulls and proper range control can eventually produce good quality beef 
cattle, both for the local market and the West Indian export trade. Breeding 



236 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4. 

experiments by the Rupununi Development Co. Ltd. favour a Hereford-Zeba 
cross, and grazing tests show that not more than an average of one animal to 
thirty acres should be carried. 

Primitive methods of stock management, enforced by economic conditions, 
and inbreeding have undoubtedly had an adverse effect ; but overstocking is the 
main factor in the deterioration of much of the stock in the Rupununi District. 
Overstocking on the open range can most effectively be overcome by spaying 
heifers, and this practice allows ot the selection of the females to be retained for 
breeding and of turning scrub heifers iuto marketable beef animals. The spaying 
of all undesirable heifers from overstocked country, and a percentage of the poor- 
er animals from stocked up areas, is now a matter of routine on the Rupununi 
Development Co’s, main station, but has still to be introduced by other owners. 



DAMAGE CAUSED TO RUM PUNCHEONS BY BORING 

BEETLES. 

BY 

L. D. CLEARE, f.r knt.s., 

Entomologist, 

Department of Agriculture, British Guiana. 


]. Introdnrtio i, 

II. Damage to new staves 

III. Damage to ‘grogged’ puncheons, 

IV. Examination of damaged staves. 

(,t) Staves from puncheons in 
the Colony. 

(b) Staves from puncheons returned 
from London. 

V Dunnage u ood. 

VI. Conclusions and recommendations. 

I. Introduction. 

The investigation dealt with here was undertaken between November 1037 
and January 1938 and was the direct outcome of a complaint received of damage 
liy boring beetles to the puncheons of a shipment of rum made to London from 
British Guiana in August 1937. 

The shipment of rum concerned comprised 141 puncheons from two sugar 
factories and was reported as having, on arrival at London, 7G puncheons 
(54 per cent.) bored by beetles so that repairs were necessary to the puncheons in 
London. The report showed that in the 7<i puncheons there were 173 bored staves. 

The puncheons were made at Georgetown, the staves being imported from 
the United States of America. 

From the first it was evident that there might be difficulty in forming a defi- 
nite opinion as to where the damage to the puncheons in question had taken place, 
for it was possible that the attack might have occurred at many points between the 
receipt of the staves at Georgetown and the final arrival of the packages in 
London. This was further added to by the absence, at the beginning, of the 
damaged puncheons so that a more extensive enquiry had to be undertaken than 
perhaps would have been necessary otherwise. 

II. Damade to New Staves. 

An, examination was made first of new staves, and stacks of staves at the 
cooperage wharf at Georgetown of varying dates of arrival were examined, while 
on 9th November a new shipment of headers was received and these latter were 
examined both at the time of their arrival and also a few days afterwards. 

At the outset it must be stated that both such staves and headers showed 
damage which was evidently the resalt of beetle attacks, and judging from the 
borings in the wood had been caused by probably at least three different species 
of inseots. In spite of this no boring beetles were found and it was evident that 
the damage had occurred some time previously. 



238 AGRICULTURAL JOURNAL OF BRITISH GUIANA- flX. 4. 


This damage was not excessive and amounted to 6.7 per cent, over the three 
lota examined. The details of these examinations are as tinder : 


Lot 

No. 

Date of 
examination 

Material 

Ex 

Ship. 

No. ex- 
amined 

j 

No. 

bored 

Per oent. 
bored 

I 

16.xi.37. 

Headers 

88. 

10.xi.37. 
(Brown spot) 

571 

41 

6.2 

II 

17.xi.37. 

Staves 

ss. 

13.x. 37. 
(Grey spot) 

370 

3G 

9,7 

III 

17.xi 37. 

Headers 

tlSvii.37. 
(Green spot) 

-11C 

- — 

1C 

3.8 


The damage in both staves and headers was usually quite noticeable and in 
many instanoes it was obvious that should such material be used in packages it 
would cause leakage. 


In staves with the smallest sized holes it was not apparent at first whether 
these were capable of causing leakage. Careful examinations were made, 
therefore, of a number of these borings by splitting and sectioning the staves, 
and in several instances it was found that even these holes of small diameter 
had gone through the staves. 

In the headers the damage, usually a larger-sized hole, invariably took the 
form of an oblique boring at the edge of the particular piece of wood, and here 
again it was obvious that should such material be built into a package there was 
likelihood of leakage resulting therefrom. 

III. Damage to ‘Grogged* Puncheons.* 

It has long been known amongst coopers in the Colony that puncheons which 
have been “skipped” and “grogged” when stored for a time, either before or 
after being repaired, develop “worms” which will in time cause leaks, and these 
worms may occur to such an extent as to cause the package to be discarded. 

The staves of these packages in the course of their storage with rum prior to 
skipping become soaked with the liquor, and in spite of the grogging still rotain 
some of the alcohol in the wood. When water is placed in these puncheons sub- 
sequently some of this alcohol is drawn from the wood, a fermenation is set up 
and beetles are attracted. 

Samples of water from grogged puncheons both at the Colonial Bond and at 
the cooperage were obtained and the alcoholic content determined. The figures 
in this connexion are given in Table I. 

•Wbe* runi puncheons have been in bond for some time defects in the puncheons such as 
broken staves necessitate a certain number of the packages being changed, the rum being 
transferred to other pundjeons ; this process is known as “skipping”. 

“ Skipping ” having taken place the old package is then ^grogged” t\e M water put in and 
retained for a period and then thrown away, 1 * 



Table I.— Alcoholic Contest of Water from Grogged Puncheons 


bAliAGE CAUSED TO RUli PUNCHEONS BY BOEING BEETLES. £30 


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240 


AGRIC GTLTUR AL JOURNAL OF BRITISH GUIANA. 


Dot. 4. 


A few such “grogged" puncheons were examined, and by carefully 
sectioning staves from one of these infested puncheons some of the beetles which 
were attacking them were secured. These beetles proved on examination to be 
a species of Xylebotm , which genus is well known as wood borers. 

The attack in such puncheons often occurs in the headers or around the 
groove where the header fits into the staves, but also in the staves themselves 
about the central area where ihe puncheon comes in contact with the ground 
when stored on its side. In most instances seen where the attack occurred about 
the centre of the stave it could be associated with some injury to the stave, 
sometimes only a small indentation, which had allowed ingress of the beetle. 

When the damage occurs in the headers, or in their immediate vicinity, the 
groove, a leak is readily formed, as may also occur if the damage is between two 
staves. When a stave is penetrated directly, however, the entrance of the beetle 
in itself may not result in leakage, for in such instances, the beetle, or its larva, 
does not penetrate beyond a point in the wood where it becomes more or less 
soaked with the contained spirit. Under such conditions, where leakage occurs 
it is invariably associated with cracks in the wood offen brought about by 
extreme heating, and the resulting burning and cracking, in the process of 
making the puncheon. 


IV. Examination of Staves from Damaged Puncheons. 

A number of staves removed from puncheons which showed beetle borings 
were examined comprising (a) staves from puncheons in the Colony and (b) 
staves from puncheons returned from London around which this enquiry started. 
These will be dealt with separately. 

(a) Staves Jrom puncheons in the Colony. A number of puncheons which 
had been shipped to a plantation from the cooperage in the latter part of 
November, were reported on arrival at the factory to be bored, and later when 
the damaged staves from these puncheons were removed and returned to George- 
town they were examined. 

These puncheons were made at Georgetown in October and shipped from 
Georgetown between the 27th and 2!Uh October, and on fith or 7th November, 
while at the sugar factory, they were observed to be bored. The shipment 
comprised 100 puncheons, and 30 of these showed "worm holes" in some of their 
staves, Twenty-eight of these damaged staves, and three header-pieces 
were received at Georgetown on 15th December, sent to this laboratory on the 
following day, and examined on 17th December. Of these staves eighteen 
were found to be damaged sufficiently to cause leakage, it is believed, and, in ten 
staves, it was not possible to be certain whether the damage was of such a 
nature as to cause leakage. 


The detailed results of this examination are given in Table II. 



DAMAGE CAUSED TO RUM PUNCHEONS B* BORING BEETLES. 241 


Table II.— Examination of Damaged Staves from Puncheons 
Ex-shipment of 27th/29th October, 1937. 


Group. 

Number of Holes. 

Outer side 
of staves 
only 

Inner 

side 

only 

Extending through j 
staves 

Total 

Plugged 

58 

Not plugged 

A — 18 staves 
damage in which 
would cause 
leakage 

' 9 

! 

1 

38 

19 

(1) 

, 124 

i 

i 

B— 10 staves 
damage may 
cause leakage 

(2) 

16 

3 

1 

1 

, 

, 

i 

19 


All of this damage had evidently occurred some time previously, and, in 
Borne instances at least, before the packages were constructed and was the same 
as that occurring in new imported staves. 

(b) Staves from puncheons returned from London. Late in December six 
puncheons were received at Georgetown from London which puncheons were 
stated to be part of the consignment complained about and to be damaged by 
beetle borers. 

On arrival these puncheons were seen and beetle borings were quite 
apparent in all, even on very cursory examination. 

At a later date, careful examinations of these packages were carried out, and 
the results of the examinations are given below. 

The marks on these puncheons showed that they were the product of two 
oooperages in Georgetown, and were as follows : 


(') In Group A of a total of 121 holes, 22 were situated under the bands of the puucheone, 
of which 10 had been plugged and 3 not plugged. 

( J ) In Group B of the 16 holes showing on the outer side of the stives, G were only 
Burfaoe holes aud had been plugged. 



fAftl-B ill. — il-ARKS ON jPtm0HBON& fesAlfafttito. 


•it — i 

Puncheon 

Estate Marks 
(Stencilled on 
top) 

Colonial Bond 
Marks 
(scribed) 

Colonial Bond Details* 

A 

1936 


13 Oct., 1936 

Pin.— 


PA 

5161 

Mark — A. 92 puncheons 


616 

Tare 176 lb. 
100 gals. 

36 

1 

coloured rum 

. 


— — 

~ _ - — ~ — 

B 

1935 

262 

13 Feby., 1935 

Pin.— 


G 

97 

33 

Mark— ^AS^. 

GO puncheons coloured rum 

C 

1936 

lil 

Ifa Bond 9 April 1936 

6 Hogshead ^MAS ^ (Pin. — ) 

% 

G, 1 

1590/95 | 

1 

| 

T. 1.2.25. 
(other marks 

1935 

46 

_ Cooperage) 

1 

1 

j 

Racked into 3 puncheons 

30 July 1937 

/ r \ R1 — 3 shipped 
1590795" 

ss. 4 Aug. 1937 

D 

1935 

A. 

1,320 

5 April 1935 

Pirn- 


<A> ! 

35 ! 

Mark — KF (?) M. 28 puncheons 



492 

1 

coloured Rum 

E 

1937 

4275 

4 Aug. 1937 

Pin.— 


ccc 

297 | 

T. 1.3.7 

; 

37 

Mark CCC. 59 puncheons 
coloured rum 

F 

P 

5173 

Date as in Puncheon A 

ft 

4 > 

R 

628 

1936 

Tare 184 lb. 

; 100 gals. 

36 

above 



DAMAGE CAUSED TO BUM PUNCHEONS B * BOBING BEETLES. 243 


Both the Colonial Bond and the estate marks on the packages showed that 
only one of the six packages contained 1037 ram. The other five contained 
either 1935 or 1936 ram. Although the package “ C ” contained 1036 rum. the 
liqnor was placed in it only in Jnly 1037, bat th package itself was evidently 
constructed in 1935 and had apparently been need at some time previously to the 
oooasion of the last shipment. All the packages, with the possible exception of 
“ C," had been in the Colonial Bond for some time prior to shipment, one since 
February 1935 (B), another sinoe April 1935 (D) and a third sinoe October 1936 (A). 

The borings in these puncheons were located almost entirely towards the 
ends of the puncheons, that is, where the puncheons tapered and not about the 
middle and greatest girth, and staves in all positions in the pnncheons were 
found to be bored. 

Further examination of the borings themselves showed that the majority 
did not extend for any depth into the staves and in fact many were only surface 
borings. Those which penetrated the staves did so always across the grain of the 
wood and often in a diagonal direction coming out on the sides of the staves 
where they were in contact with the adjacent staves, and invariably did not go 
beyond a point in the wood where it became sodden with the contained alcohol. 
Some of the borjng commenced at a point where two staves abutted and where 
there was a slight indentation which allowed ingress of the beetle. 

In two instances at least when a puncheon was broken down it was observed 
that between two staves there still existed the “ flag ” (made of the fibre from 
plantain psendostem) which had been placed there in the coopering of the pack- 
age in order to make a tight joint. And what was especially important was that 
those “flags’ 1 had been penetrated by beetle borings. 

No such borings of the “ flags” could have existed before they were put in 
place in the packages and the fact that the borings of the flags and of the staves 
coincided and were identical in every respect loft no doubt of their having 
occurred at a later date. 

In another instance there was found a hoop to which wood fibres were 
adhering, and the area of the staves immediately adjacent to this was severely 
bored. 

A very carefol and detailed examination was made then of a number of 
Individual, staves, and dissection of boring carried out. Staves from each of the 
five punoheons were thus examined. In this way, in staves from each package 
beetles were obtained which had died in their borings and which on examination 
proved to belong to the genus Xykborus. 

• 

As regards these puncheons from London* then* the facts pointed to the 
damage having occurred after the filling of the packages* and also after their 
removal from the Colonial Bond, and indeed, suggested that the damsge had 
occurred in transit, 



244 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[IX, 4. 


V. Dunnage Wood. 

Suspicion fell upon the dunnage -wood used in storing the puncheons on 
shipboard. Accordingly, a stack of this dunnage in the vicinity of the cooperage 
and shipping wharf was examined. 

This dnnnage is comprised of a miscellaneous collection of local wood, 
among which examples of Congo Pomp, ( Cecropia spp.) Hog Plum ( Spondias 
Monbin L.) and Shiroua, ( Nectandra 8pp.) were seen. 

Ample evidence was soon obtained that some of this wood was severely 
attacked by beetles, and further examination disclosed that beetles of the genus 
Xyleborus constituted the majority of these insects. 

In this material the Xyleborus attack was at the time of my examination still 
active and there was little difficulty of obtaining live beetles although it was 
evident that the stack had been in position for some weeks. 

VI, Conclusions and Recommendations. 

From what has been stated above under the different sections it will be seen 
that beetle damage as found in the present investigation falls into two distinct 
categories, namely (i) that occurring in new staves, and (ii) that occurring in 
puncheons in one form or another. 

(i) Damage occurring in new staves. Little need be said as regards this. 
It has been stated already that it is the result of beetle attacks before the arrival 
of the staveB in the Colony, and probably occurred at the point of logging 
operations. Sufficient it is not active when the staves are received in British 
Quiana, and as the percentage of staves damaged is not high the allowance made 
by the suppliers (1 ,200 staves are given per mille rate) is ample to allow for 
rejections arising from this cause. Incorporation of staves damaged in this 
manner into puncheons, as previously pointed out, would in many instances 
cause leakage. 

(ii) Damage occurring in puncheons. In grogged puncheons which were 
in storage and in the puncheons returned from London, as has been stated 
previously, Xyleborus beetles were found to be the cause of the damage. 

Beetles of the genus Xyleborus are well known as timber borers in different 
parts of the world. On account of their habit of feeding on certain fungi which 
grow in the tunnels which they make in the wood an essential for their exis- 
tence is that the wood whioh they bore must be at least moist 1 , and conversely 
one of the characteristics of these beetles is that they do not attack dried and 
Reasoned wood. 

Accordingly, normally it would not be expected that these beetles would 
attack rum puncheons. If, however, the exterior of a puncheon, either empty, 
artly filled with weak alcoholic solution or even with nun itself, is wet for 



DAMAGE CAUSED TO RUM PUNCHEONS BY BORING BEETLES. S45 

gome time, or oomes in direct with some substance itself more or less wet over a 
period of time long enough to allow the wood of the puncheon to take up 
moisture such a puncheon might be attacked by Xyleborm beetles. 

The damage caused to grogged puncheons was not investigated in the 
present instance beyond the point of establishing such damage and ascertaining 
the insect concerned. 

As regards the puncheons returned from London, the fact that the attack 
was not seen when it first occurred and in an active state, and that several weeks 
had elapsed before the packages were examined, any conclusions arrived at in 
this connection must necessarily be of a circumstantial nature. 

With this reservation then, it may be said that as the result of investigations 
and the conditions observed, and the examinations made of the puncheons, 
there is reason to believe that the damage to these puncheons occurred after the 
packages were removed from the Colonial Bond, and in all probability while 
they were in transit to London. Further, that such damage was caused by 
Xylrborus beetles ( Xyleborm badius Eich. Det. K. E. Schedl, through Imperial 
Institute of Entomology, London) some of which were found in the borings in 
the puncheons; that such beetles were breeding in all probability in the dunnage 
wood used with this shipment of rum and that the puncheons were infested and 
damaged by such beetles. 

The measures to be adopted with regard to damage to puncheons in 
transit and arising from the dunnage wood is, of course, a change in the material 
used as dunnage. In this connection, it was suggested that perhaps wallaba 
{.Eyerua spp.) “ ton-wood ” might be used instead of the present miscellaneous 
“cord-wood.” This is not recommenced as the sapwood of wallaba also has 
been observed to be attacked by several spe cies of Xyleborm beetles. 



SUMMARY OF AGRICULTURAL LEGISLATION IN 
BRITISH GUIANA. 


INDEX. 

Part I. 

GENERAL AND MISCELLANEOUS AGRICULTURAL LEGISLATION, 

Agriculture — General. 

The Board of Agriculture Ordinance , No. 26 of 1934. 

The Crops and Livestock Registration Ordinance, No. 22 of 1917, (Cap. 159). 

The Crown Lands Regulations 1919, made under section 11 of the Ct'own 
Lands Ordinance, No. 32 of 1903, (Cap. 171). 

The Lands d Mines and Forestry Department Ordinances related to Agriculture: 

The Lands Mines Department Oidmance, No. 31 of 1903, 
(Cap. ICG). 

The Land Surveyors Ordinance, No. 20 of 1891, (Cap. 167). 

The District Lands Partition and Re-allotment Ordinance, No 
16 of 1926, (Cap. 169). 

The Crown Lands Ordinance , No. 32 of 1903, (Cap. 171). 

The Ciown Lands Resumption Ordinance, No. 30 of 1905, 
(Cap. 172). 

The Polder Ordinance, No. 25 of 1910, (Cap. 174). 

The Forestry Ordinance, No. 29 of 1927, (Cap, 176), 

Sugar. 

The Sugar Experiment Stations Ordinance, No. S3 of 1937. 

The Sugar (Regulation of Prices) Ordinance, No. 15 of 1930. 

The Sugar ( Temporary ) Excise Duty Ordinance, No. 2 of 1932 amended ly the 
Sugar (Temporary) Excise Duty ( Amendment ) Ordinance, No. 5 of 1987. 

The Sugar (Temporary) Excise Duty Regulations , 1932 . 

Tlfo Sugar Quota Ordinance, No. 19 of 1937. 

The Molasses (Disposal) Ordinance, No. 28 of 1981. 

The Molasses (Disposal) Ordinance, No. 41 of 1983, • 



StfjfMARY OF AGRICULTURAL LEGISLATION IN BRITISH GUIANA 24 f 

Bice. 

The Rice (Export Grading) Ordinance, No, 18 of 1930 amended by the Bice 
( Exjtort Grading ) Ordinance, No. 40 of 1932. 

The Rice ( Export Blending and Grading ) Regulations, 1934 amended by the 
Rice (Exjiort Blending and Grading) Regulations (No. 3), 1934. 

The Rice (Exjwrt Trade ) Ordinance, No. 17 of 1935. 

The Rice (Export Trade) Regulations, 1935. 

The Rice Factories Ordinance, No. 26 of 1933. 

The Rice Factories Rules, 1934. 

Coconuts. 

The Coconut Products ( Control ) Ordinance, No. 36 of 1935. 

The Coconut Products Rules, 1936. 

Narcotics. 

The Tobacco Cultivation (Repeat) Ordinance, No. 4 of 1930. 

The Indian Hemp and Datura Ordinance, No. 36 of 1924, (Cap. 190). 

The Opium Ordinance, No. 13 of 1926, (Cap. 191). 

Agricultural Credit. 

The Plantation (Proprietors) Government Loans Ordinance, No. 9 ot 1893, 
(Cap. 158). 

The Agricultural Relief Ordinance, No. 20 of 1896, (Cap. 152). 

The Rice Growers Loans Ordinance, No. 2 of 1922 (Cap. 155). 

The Co-ojK’rativc Credit Banks Ordinance, No, 28 of 1933. 

The Co-operative Credit Banks Regulations, 1933. 

The Co-operative Credit Banlcs Regulations, 1937. 

« 

The Co-ojierative Credit Banlcs (Amendment) Ordinance, No. 13 of 1938. 

Miscellaneous, 

The Public Gardens and Agricultural Shows Ordinance, No. 34 of 1935. 

The Government Botanic Gardens Regulations , 1936. 



248 


AGRICULTURAL JOURNAL OP BRITISH GUIAltA. 


flX, 4. 


PART II. 

LEGISLATION RELATING TO INSECT PESTS AND FUNGUS DISEASES. 

The Plant Diseases & Pests { Prevention ) Ordinance , No. 37 of 1935. 

(A) Regulations and Orders Relating to Pests and Diseases 
Present in the Colony. 

The Plant Diseases and Pests ( Notification) Regulations, 1936. 

Order re Coconut Caterpillar { Brassolis sophorae L.) and Witch Broom ( Maras- 
mius p erniciosus Stahel). 

(B) Orders and Notices Relating to the Importation and 
Exportation of Plants, Fruit, Seed, etc. 

Sugar Canes, Grasses, Soil, Banana and Plantain Suckers. Order re 
importation of, 

Plants, seeds, etc. Order re examination of, 

Mediterranean Fruit Fly ( Ceratitis cupitata). Orders to prevent intro- 
duction of 

Citrus. Orders prohibiting importation of from United States of America and 
West' Indian Islands. 

Raw Coffee. Order prohibiting importation of. 

Pimento. Order prohibiting importation of, from Jamaica, 

Padi. Order prohibiting importation of, 

Part III. 

LEGISLATION RELATING TO LIVESTOCK, BEES AND WILD BIRDS. 

Livestock— General. 

Pounds Ordinance, No. 1 of 1866, {Cap. 93). 

Pound Fees Rules and Regulations, 1937. 

Cattle Stealing Prevention Ordinance, No. 3 of 1877, {Cap. 91). 

Cattle Trail ( Tolls) Ordinance, No. 16 of 1929. 

Cattle Foods. Notice re Importation of, 

Veterinary. 

The Animals Diseases Ordinance, No. 29 of 1936. 

The Animals Diseases Regulations, 1937. 

Importation of Animals. Order re, 

Beer. 

The Importation of Bees Ordinance, No. 38 oj 1935. 

The Importation of Bees Regulations, 1936, 

The' Importation of Bees {Amendment) Ordinance, No. 18 of 1936. 

Wild Birds. 

The Wildr Birds Protection Ordinance, No. 81 of 1919, {Cap, 278), 



A SUMMARY OF AGRICULTURAL LEGISLATION IN 
BRITISH GUIANA. 


Part I. 

GENERAL AND MISCELLANEOUS AGRICULTURAL 

LEGISLATION. 


AGRICULTURE— GENERAL. 

The Board of Agriculture Ordinance , No. 26 of 1934. 

Under this Ordinance there is established an advisory Board of Agricnltnre 
consisting of the Director of Agriculture who shall be Chairman, the Deputy 
Director of Agriculture who shall be Vice-Chairman and not more than seven 
other persons who shall be appointed by the Governor. Every appointed 
member shall hold office for three years, but shall be eligible for re-appointment. 
The Governor may appoint some person to be a member in place of an appointed 
member who is absent on leave (which may be granted by the Governor) or 
owing to death or other cause. The Board shall meet at least onoe every three 
months, or at any time at the request, in writing, of three members Btating the 
purpose for which the meeting is required. 

Under this Ordinance the Board of Agriculture Ordinance, No. 27 of 1920, 
(Cap. 150) is repealed. 

The Crojis and Livestock Registration Ordinance , No. 22 of 1917, (Cap. 159). 

By this Ordinance the occupier of any land or the owner of any live- 
stock is required to give, before the last day of January of each year, returns 
on the approved forms showing the acreage of land under cultivation at the 
date of the return, and the crops and produce thereof reaped during the year 
ending on that date, also the number of animals kept at the date of the return, 
and their increase during the year ending on that date. 

The Crown Lands Regulations 1919, made under section 17 of the Croton 
Lands Ordinance, No. 32 of 1903 , (Cap. 171) contain a number of regulations 
concerning Agriculture. 

Part I deals with Applications for Grants or Leases, Licences or Permissions 
of Crown Lands and the Renewal, Revision, Transfer, etc., of the same. Part 
II is concerned with surveys, where such are required, and Part IV deals with 
Grants to small cultivators. 



&)6 AGRICULTURAL JOURNAL OF BRITISH GUlANA. [iX, L 

Part V covers leases both for agricultural purposes and for grazing purposes, 
and Part VI deals with Permission for Grazing Areas in the interior. 

Part VIII embraces Leases and Licences to cut wood and Part IX Lioenoes 
to collect Balata and Gums, etc. Regulations 70 and 71 et scq in this latter part 
prescribe for the collection of Orchids and other Forest Products such as 
Haiari (Lonchocarpw spp.), Tonka Beans, etc., for which permission has to be 
obtained from the Commissioner of Lands and Mines. 

Part X, Regulations 80 et scq deal with the removal of sand or shell from 
Crown Lands. 

LANDS AND MINES AND FORESTRY DEPARTMENT ORDINANCES RELATED 

TO AGRICULTURE. 

The following Ordinances may under certain circumstances concern the 
Department of Agriculture. 

The Lands and Mines Department Ordinance, No. 81 of 1903, ( Cap. 1GG) 
makes provisions as to Crown and Colony Lands. 'The Land Surveyors 
Ordinance, No. 20 of 1891, (Cap, 167) covers the making of surveys, and the 
District Lands Partition and lie-allotment Ordinance, No 1G. of 1920, (Cap. 169) 
conoerns the partitioning and re-allotment of land. 

The Crown Lands Ordinance, No. 32 of 1903, (Cap. 171) deals with the 
leasing, etc., of Crown Lands, and contains (section 17 (f>) ) Regulations as to the 
Rupununi Cattle Trail and the payment of Tolls thereon. Further regulations 
made under this Ordinance have been dealt with above in the section concerning 
the Grown Lands Regulations, 1919. 

The Crown Lands licsump/ion Ordinance, No. 80 of 1906, (Cap. 172) deals 
with land which has been abandoned for more than 8 years, and the ownerB of 
which are called upon to prefer their claims, and The Polder Ordinance, No. 25 
Of 1910, (Cap. 174) deals with the creation of Polders. 

The Forestry Ordinance, No. 29 of 1927, (Cap. 176) covers the demarcation 
and regulation of Forest Reserve areas, and the unlawful possession of Forest 
Produce. 

SUGAR. 

The Suyar Experiment Stations Ordinance, No. 33 cf 1937. 

This Ordinance makes provision for a Committee, consisting of six persons 
immediately connected with the Sugar Industry, together with the Director of 
Agriculture as Chairman, to maintain and manage such Sugar Experiment 
Stations as may be deemed necessary, and to appoint such executive officers as 
maj^ba required. Expenses shall be paid out of a Sugar Experiment Stations 
Fund and a rate calculated on the acreage of land under sugar cane cultivation is 
levied on the Sugar Plantations, 60 per cent, of the amount due being payable on or 



A SUMMARY OF AGRICULTURAL LEGISLATION IN BRITISH GUIANA. 251 


before January 31 and 40 per cent, on or before June 30. Where investigation of 
an extraordinary nature becomes necessary, an additional rate may be levied. 
The Committee may make regulations, subject to the approval of the Governor* 
in-Council, to carry out the provisions of the Ordinance. 

Under this Ordinance the previous Sugar Experiment Stations Ordinances 
No. 41 of 1932 and Nos. 14 and 31 of 1934 are repealed. 

Sugar (Regulation of Prices) Ordinance, No. 15 of 1930. 

By this Ordinance the Governor is empowered to fix the maximum price 
for which the various grades of sugar manufactured in the Colony may be 
retailed. 

Sugar ( Temporary ) Excise Duty Ordinance, No. S of 1932 amended by the 
Sugar ( Temporary) Excise Duty ( Amendment ) Ordinance, No. 5 of 1937. 

These Ordinances impose an excise duty at the rate of 90 cents on every 
100 pounds weight of all sugar manufactured in the Colony and sold for home 
consumption. The first Ordinance provides for the keeping of the necessary 
books by Sugar manufacturers and producers, and limits the price of sugar 
liable to duty. It also sets out the method of payment of duty. 

Sugar ( Temporary ) Excise Duty Regulations , 1932. 

These Regulations, made under the provisions of Section 2 (1) of the Excise 
(Regulations) Ordinance, No. 21 of 1903, (Cap. 40) stipulate more fully the 
form of books to be kept in accordance with the above Ordinance, (No. 2 of 
1932). They also specify that all Sugar manufactured at a factory must be 
packed in bags containing either 230 pounds, 125 pounds or 112 pounds of 
sugar nett weight. 

The Sugar Quota Ordinance, No. 19 of 1937, 

This Ordinance restricts and regulates the export of Sugar from the Colony 
by tho allocation to local manufacturers of quotas for exportation. Sugar may 
only be exported under licence and export certificate. 

Molasses ( Disposal ) Ordinance, No. 23 of 1931. 

This Ordinance makes it compulsory for any persons disposing of molasses, 
except for export from the Colony, to keep a Molasses disposal book in which 
must be recorded details of sale. A statement of these sales must be submitted 
to the Commissary monthly. No person may sell or receive more than two 
gallons without a certificate, 

Molclsses ( Disposal ) Ordinance, No. 41 of 1933. 

This Ordinance makes it obligatory for any person receiving Molasses, 
except for export purposes, to state in Writing the purpose for which he desires 
to obtain the molasses. No person may sell or receive more than two gallons of 
molasses excgpt there be also provided a certificate of the sale. 



252 


agricultural journal of British gtjiana. 


[IX, 4. 


RICE. 

The Rice {Export Grading) Ordinance , No. IS of 1930 amended by the Rice 
(Exjtort Grading) Ordinance , No. 40 of 1932. 

These Ordinances prohibit the export of Rice without inspection and grading 
and stipulate that shipments of Rice for export shall be blended so as to ensure 
that the contents of each individual container of a consignment are uniform. 
Inspectors to enforce these laws are to be appointed by the Director of Agricul- 
ture with the approval of the Governor-in-Council. Provision is made for the 
appeal to the Director of Agriculture by any aggrieved person against any 
decision of an Inspector. 

Rice (. Exinjrt Blending and Grading) Regulations , 1934 amended by Rice 
( Export Blending and Grading) Regulations {No. 3 ), 1934. 

The grades of Rice are described in a schedule attached to the Regulations 
and in the amendment. No Rice other than Broken and Super Broken may be 
submitted for grading unless it has been previously blrended. No person shall 
blend Rioe unless he has first obtained a licence for the purpose from the Director 
of Agriculture arfd such licensed blenders shall be registered. A licence ceases 
to have effect at the end of every financial year, but may bo renewed for the 
ensuing financial year. The Director may, if he considers fit, remove from the 
register the name of any blender. The blender’s foe is limited to two cents per 
100 pound bag and four cents per bag over 100 pounds. A set of guide samples 
according to grades will be supplied by the Department of Agriculture to regis- 
tered exporters of Rice. Rice for export shall be delivered at specified wharves 
and in new bags. Application for grading must be made to the Inspector not 
less than 24 hours prior to shipment. Each application for grading must be 
accompanied by the certificate of a registered blender certifying that the Rice has 
been blended and must be signed by the Secretary of the Rice marketing Board 
before they are delivered to the Inspector. Consignments of Rice must be 
pointed out to the Inspector by the owner or his agent on the wharf and the 
Inspector shall examine by samples a minimum of 25 per cent, of the bags. The 
consignor shall pay a grading fee at the rate of one cent per bag of 100 pounds 
or less and at cents per bag of more than 100 pounds. After samples have 
been taken from a consignment the exporter shall present his Customs specifica- 
tion form, on which is indicated the name of the wharf, to the Inspector for 
certification. At the timo of exportation this form shall then be presented 
to the wharfinger who will attach a further certificate stating that the Rice 
specified is the same as that examined by the Inspector. The specification form 
and Wharfinger’s certificate shall be delivered to the Customs Offioer at the time 
of shipment. If Rice has been graded and is removed from the place of delivery 
without being shipped it must be regraded before export. A grading certificate 
remains valid for 14 days ; it may be renewed under the authority of the 
Director of Agriculture. The exportation of Rice infected with insect pests or 
fungi, or with objectionable odour, is forbidden, and provision is ^made for the 



A SUMMARY OF AGRICULTURAL LEGISLATION IN BRITISH GUIANA. 253 


removal of each Bice, All Bice exported mast conform to the standards of the 
grades described in the Schedule attached to the Regulations and in the 
Amendment. Bice intended for special markets 'will not be allowed to be 
exported unless it conforms to the requirement of those marketB. 

Under these Regulations the Rice (Export Blending and Grading) Regula- 
tions, 1932 and 1933 are revoked. 

The Rice {Export Trade) Ordinance, No. 17 of 1035. 

This Ordinance provides for the establishment of the British Gniana Rice 
Marketing Board, a corporate body which may sue and be sued in its corporate 
name. The Board is to consist of the following members : — 

(a) two officers in the public service appointed by the Governor. 

(b) five other persons appointed by the Governor-in-Council. 

The Board may, with the approval of the Govemor-in-Council, appoint a 
salaried secretary and may employ such other officers and servants as required. 
An advisory Committee consisting of six persons shall be appointed by the 
Governor-in-Conncil to advise the Board on the price of Rice and on all other 
matters in which the Board may seek its advice. The Board may make regulations 
to fix the price of Rice, prescribe the form of contract for the sale of Rice, grant, 
renew or Buspend exporters’ licences, approve of exporters’ sgentsand generally 
take action to improve the Rice Trade. Ihe Board is empowered to collect fees 
which are to constitute the revenue of the Board, out of which expenses shall be 
defrayed. Specifications are made in regard to the terms of contracts and 
and licences to export Rice. No person may export Rice unless he holds the 
Board’s licence, nor without the Board’s permission sell Rice at a price below that 
fixed by the Board. 

The Rice (Export Trade) Ordinances, Nos. 47 of 1932 and 21 of 1933 are 
revoked. 

Rice {Export Trade) Regulations , 1035. 

These Regulations concern the fixing of the prices of export Rice, the grant- 
ing of credit to buyers and the remuneration payable to exporters’ agents. 
They stipulate the manner in which contract sales may be effected, and provide 
for the proper appointment of agents. Every bag of Rice for export shall be 
clearly marked with the grade of the Rice therein. 

The Rice Factories Ordinance , No. 26 of 1933. 

ThiB Ordinance stipulates that before the erection of a Rice factory a 
certificate stating that the premises are fit to be used as a Rice Factory, having 
regard to public health and sanitation, must be obtained from the proper 
authority. After this certificate is obtained, application may then be made to 
the Commissioner of the District for a licence for which a fee of $1.00 is payable 
and which will expire on the 1st of December of each year. Rice may not be 
manufactured except by the holder of such licence. Where a Commissioner has 
refused to ggant a licence, appeal may be made to the Governor-in-Council. If 



&54 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [iX, 4. 

a licence is to be transferred, application in writing most be made by the 
transferor and transferee to the Commissioner. The holder of a licence must 
keep proper books at the Bice factory showing the quantities of Padi received 
and the amounts of Bice mannfactnred and must issue and record receipts for 
such Padi. During January and July of each year returns showing the matters 
recorded in these books must be made to the Commissioner. For the purpose of 
this Ordinance, a bag of Padi and Bice are taken as weighing 143 pounds and 180 
pounds gross, respectively. 

Authorised persons are empowered to inspect a factory, any Padi or Bice on 
hand, or any books kept under this Ordinance. It is prohibited for anyone to 
sell, purchase or receive Padi for the manufacture of Rice except at a price 
calculated at a bag of 143 pounds gross. 

The Bice Factories Buies, 1034. 

These rules specify in detail the form of books and receipts to be uBed under 
the above Ordinance. 

COCONUTS. , 

The Coconut Products ( Control ) Ordinance , No. 36 of 1035. 

This Ordinance regulates the manufacture and sale of products obtained 
from the kernel of the Coconut. 


Part I. 

Coconut Products may only be manufactured by a licenced manufacturer 
and sold by a licenced broker, the licences to be obtained in each case from the 
Commissioner of the District, both costing $5.00, and expiring on December 
31 of each year. Where application for a licence is refused, appeal may be 
made to the Governor-in-Council, who may also suspend or revoke licences. 
Every Copra or Crude Coconut Oil producer shall be registered by the Commis- 
sioner of the district, for a fee of 24 cents, and no unregistered person may 
produoe Copra or Crude Coconut Oil. Copra may only be sold through or 
exported by a broker, and a broker may not sell Copra to any person in the 
Colony who is not a manufacturer. The Governor may from time to time 
prescribe the percentage of the quantity of Copra under control of a broker 
which may be exported during any period of 3 months, 

Part II. 

A Brokers* Board shall be established consisting of all licensed brokers and 
two Copra producers appointed by the Governor-in-Council. A Secretary shall 
be appointed and meetings held onoe a week, Charges to defray the expenses 
of the Board shall be fixed by the Board, and not exceed 20 oents per ton of 
Copra sold. The Board shall at its weekly meetings fix the amonnt to be 
advan^pd by brokers to producers in respect of Copra delivered to the brokers, 
the amount of this advance being based on the price of Copra as fixed by the 
Govemor-in-Council. The brokerage charge shall be at the rate of 25 cents for 
100 pounds. of Copra, Proper bqok* shall be kept by brokers showing the 



A SUMMARY OP AGRICULTURAL LEGISLATION IN BRITISH GUIANA. 235 

purchases and sales of Copra, and quarterly returns made accordingly to the 
Commissioner of the district. No person may aot as a broker unless a sum of 
$5,000 is deposited with the Colonial Treasurer or a banker’s undertaking given 
fop this amount. 

Part hi. 

The following excise duties shall be levied on Coconut Products manu- 
factured and consumed in the Colony, to wit, 12 cents per gallon of deodorized 
Coconut Oil and 42 cents per 100 pounds of Lard Substitute. Books shall be 
kept by manufacturers of Coconut Products, showing the amount and origin of 
produots received and manufactured, and monthly returns made accordingly to 
the Commissioner of the district. Producors of Copra and Crude Coconut Oil 
shall keep similar books. 

Part IV. 

No manufacturer may pay less for Copra than the price fixed from time to 
time by tho Govemor-in-Council, nor less than an equivalent price for Crude 
Coconut Oil, reckoning 100 pounds of Copra = 6§ gallons Coconut Oil, Provision 
is made to cover cases in which a manufacturer is also a producer of Copra or 
Crude Coconut Oil. Tho Governor may prescribe standards of quality and fix 
maximum wholesale and retail prices within the Colony. Crude Coconut Oil 
may not be exported except under licence. Provision is made for tho examina- 
tion of samples of Crude Coconut Oil and other coconut products by the Govern- 
ment Analyst. Authorised persons may inspect factories and brokers’ premises 
and examine the books at all reasonable times. No coconut product exceeding 
1 gallon or 10 pounds may be removed except by permission of a Commissioner, 
who may, however, authorise a manufacturer or rotailer to remove coconut 
products from his premises at his own discretion. 

Under this Ordinance tho Copra Products (Sale and Manufacture) Ordinan- 
ces, Nos. 31 of 1933 and 23 of 1934 are repealed. 

The Coconut Products Rules, 1936. 

These rules prescribe the form of licences, certificate of registration, register, 
books and removal permits called for under the above ordinance. 

NARCOTICS. 

Tobacco Cultivation ( Repeal ) Ordinance, No. 4 of 1980. 

This Ordinance repeals tho Tobacco Cultivation Ordinance, No. 14 of 
1912, (Cap. 161) which controlled the cultivation and manufacture of Tobacco. 

The Indian Hemp and Datura Ordinance, No. 36 of 1924 and the Opium 
Ordinance, No. 18 q) 1926. (Cap. 190 and Cap. 191).* 

Under these Ordinances it is unlawful to cultivate the Indian Hemp 
( Cannabis sativa or O. indica), Datura ( Datura fastuosa, D. stramonium, 
D. motel and their allies) or the Opium Poppy t Papaver somm/erwn), 



&56 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4. 

AGRICULTURAL CREDIT. 

The Plantation (Proprietors) Government Loans Ordinance, No. 9 of 189S, 

(Cap. 158). 

This Ordinance gives the right of summary recovery over by one 
co-proprietor of a plantation paying Government loan (i.e. loan made from 
public moneys under the sanction of the Legislative Council) for another 
co-proprietor. 

The Agricultural Relief Ordinance , No. 20 of 1896 , {Cap. 152). 

This Ordinance creates a preferent crop lien on the crop or crops to be 
reaped during the then current year for loans or advances made to the owner of 
land (/>., cane plantation and other land cultivated for at least one annual crop) 
for maintaining cultivation and management, machinery and buildings, purchase 
of supplies and payment of taxes, etc., when recorded in prescribed loim by 
the Registrar of Deeds. The lender is exempt from obligation to see to the 
application of the loan, and has a right to inspect the crops pledged. Account 
must be kept by the owner of the application of the loan. Misapplication of 
the loan is de'emed a felony. 

The Rtre Groieer^' Loans Ordinance , No. 2 of 192?, (Can. 155). 

This Ordinance authorises the Colonial Treasurer to advance out of public 
funds to registered Co-operative Credit Banks any sums not exceeding one 
hundred and fifty thousand dollars in the aggregate for the special purpose of 
making loans to Rice growers (whether members or not members of the banks) 
to be used by the borrowers for reaping, bagging and transporting Padi to the 
place of storage appointed by the banks. The Ordinance covers on the banks a 
preferent lien on such Padi, and a bank may sell the Padi, or mill it into Rice 
and sell it for the recovery of loan and interest together with any expenses of 
storage, milling and sale, all of w T hich may be recovered by parate execution 
also. Misapplication of loans is deemed an offence. 

The Co-operative Credit JBanlcs Ordinance , No. 28 of 1933. 

This Ordinance has been enacted to make better provision for the constitu- 
tion and management of Co-operative Credit Banks and provides for the appoint- 
ment by the Governor of a Board, with the Director of Agriculture, Chairman, 
for the general superintendence of all banks, and a Registrar of banks, who is 
also secretary of the Board. 

Part I of the Ordinance stipulates that a bank which may be registered 
must be a bank established for making loans to its members for the development 
o| 4 their land or for some other industrial pursuit. Provisions a/e made for the 
conditions and acknowledgment of registration, appeal from refusal to register, 
effect of acknowledgment of registration, incorporation of banks with limited 
liability power to acquire land and dispose of property, keeping of register of 
banks, and cancellation and suspension of registration by the Board, 



A. SUMMARY OP AGRICULTURAL LEGISLATION IN BRITISH GUIANA. 257 

Part II prescribes (a) Powers and functions of the Board ; (b) Status of 
person appointed to be a member of a committee to represent the Board ; (c) 
Rights and powers of the Board on taking over the management of a bank ; 
(d) Return of management. 

Part III deals with the operations of the banks in regard to (a) Loans to 
banks from public funds ; (b) Loans by banks a preferent charge on borrowers’ 
property ; (c) Remedy for debts from members ; (d) Audit ; (e) Report by 
Board to Government. 

Part IV treats of dissolution and winding up of banks. 

Part V stipulates offences and imposes penalties. 

Part VI enables the Governor to make regulations for giving effect to the 
Ordinance and prescribing rules for the government of the banks. 

The Co-operative Credit Banlcs Regulations, 193-3. 

Under these Regulations model rules are provided for the banks. 

The Co-operative Credit Banks Regulations , 1937. 

These have revoked Rule IX (b) of the Rules for Co-operative Credit Banks 
in the Schedule to the Co-oporative Credit Banks Regulations, 1933, as amended 
by the Co-operative Credit Banks Reglations, 193G, and substituted a new Rule 
IX (b) therefor in regard to the disposal of a bank’s revenue. 

The Co-operative Credit Banks (Amendment) Ordinance, No. 13 of 1938. 

This Ordinance amends Sections 2 and 18 (2) of the Co-operative Credit 
Banks Ordinance, 1933, in certain particulars to restore to the Banks the pref- 
erent claim provided under the Ordinance which was affected by the provisions 
of the Deeds Registry Amendment Ordinance, No. 4 of 193G. 

MISCELLANEOUS. 

The Public Gardens and Agricultural Shows Ordinance, No, 34 of 1935. 

This Ordinance enables the Governor-in-Council to make Regulations 
concerning the Government Botanic Gardens and Government? Agricultural 
Stations and also with respect to the holding of Agricultural Shows. 

The Government Botanic Gardens Regulations, 1936. 

These Regulations, made under the Public Gardens and Agricultural Shows 
Ordinance, provide for the control of persons and vehicles in the Gardens. 



258 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[IX, 4. 


Part II. 

LEGISLATION RELATING TO INSECT PESTS AND 
FUNGUS DISEASES * 

The Plant Diseases and Pests (Prevention) Ordinance, No. 87 qf 1933, 
(under which the similar Ordinance, No. 2G of 1920 is repealed) gives the 
Governor-in-Council power to make Orders and Regulations controlling the 
importation and exportation of plant material and authorising the necessary 
measures to deal with outbreaks of Pests or Diseases within the Colony, 
Importation of plants may also be controlled by orders made under tho Customs 
Ordinance No. 7 of 1884, (Cap. 33). 

(A) REGULATIONS AND ORDERS RELATING TO PESTS AND 
DISEASES PRESENT IN THE COLONY. 

The following aro issued under the Plant Diseases and Pests (Prevention) 
Ordinance:-— 

Plant Diseases and Pests (Notification) llegulalions, 1930. 

The Governor-in-Council may by order published in the “ Official Gazette ” 
declare any disease or post to be a notifiable disease or pest, whereupon, in 
accordance with the Ordinance, the owner or occupier or person having charge 
or management of land on which such a disease or pest occurs must notify tho 
Director of Agriculture in writing and must subsequently carry out such steps 
as the Director of Agriculture may order for the eradication or prevention of 
spread of the disease or pest. The owner is liable for expenses incurred, though 
payment of part or all of these may be dispensed with at the Director’s discre- 
tion. The decision of the Director as to the presence or identification of a 
notifiable disease or pest is final. 

Order in Council No. 550 dated April 2, 1936, published in the “ Official 

Gazette ” of April 11, 1930. 

By this Order Coconut Caterpillar (Brassolis sophorae L.) was declared a 
notifiable Pest throughout the Colony and Witch Broom ( Marasmius 
perniciosus Stahel) was declared a notifiable disease in the North West District 
of the Colony. 

(B) ORDERS AND NOTICES RELATING TO IMPORTATION AND 
EXPORTION OF PLANTS, FRUITS, SEED, ETC. 

Order in Council No. 551 dated April 2, 1986, published in the “ Official 

Gazette ” of April 11, 1986. 

Ifjhis Order prohibits the importation into the Colony of Sugar Canes and any 
planter parts thereof, of plants of grasses of any kind, and of earth or soil or 
an y packages or coverings which contain o r have con tainedearth or soil. It also 

•A summary of Plant Importation and Exportation Legislation in British Guiana and 
the Caribbean Colonies was published in Agricultural Journal of B.G. IX, 1, p. 25, 1938, 



A SUMMARY CF AGRICULTURAL LEGISLATION IN BRITISH GUIANA. 259 


prohibits the importation of banana and plantain suckers without the written 
authorization of the Director of Agriculture. The provisions of this Order do 
not, however, apply to importations made by the Director of Agriculture for 
scientific purposes. 

Order in Council No. 552 dated April 2, 1036 and published in the “ Official 

Gazette ” of April 11, 1936. 

This Order provides that all living plants, seeds, cuttings, bulbs or other 
plant parts intended for propagation, which may be imported into the Colony, 
shall be examined by an authorized inspector, who> if he passes the same for 
importation, shall issue to the Customs Officer a certificate on the recognised 
form, permitting entry. 

Under this Order also, where a certificate of examination is required by tbe 
consignee of living plants or plant products exported from the Colony, the same 
Shall be provided on the recognised form by an authorised inspector. 

Mediterranean Fruit Fly ( Ceralitis capitala). 

Order in Council No. 767 dated May 19, 1930 and published in the “ Official 
Gazette ” oj May 31, 1930, amended by Order in Council No. 235 dated August 
20, 1934 and published in the ‘‘ Official Gazette ” of August 25, 1934. 

These Orders, made under the Castoms Ordinance of 1884 (Cap. 33) and 
Amendment Ordinance, 1911, with the object of preventing the introduction of 
the Mediterranean Fruit Fly ( Ceratitis capitata) prohibit tbe importation of 
fruits (excepting plantains, nuts and preserved fruits) and vegetables (excepting 
onions, potatoes and preserved vegetables) from all countries except the British 
Isles, Canada, and the British West Indies, not including Bermuda and the 
Bahamas, bnt allow the importation of Pineapples, Yams, Sweet Potatoes, 
Tannias, Eddoes and DasheenB from Dutch Guiana. 

Citrus. 

Order in Council No. 862 dated June 8, 1937, and published in the “ Official 
Gazelle ” of June 19, 1937 and Order in Council No. 868 dated June 2, 1938 
andpublishcd in the " Official Gazette " of June 11, 1938. 

The first of these orders prohibits the importation into the Colony of Citrus 
material, including fruit, from the United States of America on account of the 
danger of introducing Citrus Canker ( Phytomonas citri ) and the second prohibits 
the importation of Grapefruit from Trinidad and all citrus fruits from the 
remainder of the British West Indies owing to the presence of Citrus Scab 
(Elsinoe'Fawcetti) on Grapefruit in Trinidad, and of Citrus Weevil ( Diaprepes 
spp.) in other of the British West Indies. 

Coffee 

Order in Council No. 646 dated November 9, 1937 and published in the “ Official 

Gazette ” of November 13, 1937, 

This Order prohibits the importation of raw coffee from all countries on the 
continent of tenth America and from all other countries unless the Director of 



360 AOHICtTLTOftAL JOtTSKAt OF iHUtlKH «t»ASA» flX, 4. 

Agriculture is satisfied that it is from a oountry in whioh the Coffee Berry-Borer 
(Stephanoderes hampet) is unknown. 

PlMEWTO 

Notice No. 852 , published in the “ Official Gazette” of December 5, 1988. 

Owing to the occurrence of Rust Disease of Pimento and of the Bay Tree 
(Punenta acris ) in Jamaica, the exportation of the Pimento Plant or any part 
thereof, except the dried berries used for commerce, is prohibited in Jamaica, 
and their importation therefrom into this Colony is prohibited in accordance. 

Rick Seed (padi). 

Qj'dei in Count if No. 422 dated Aw/nsf 17, 1988 and published in the 
“ Official Gazette” of St pi an bn 21, 193S. 

This older prohibits the importation of Rice Heed (l'adi) without the 
written authorisation of the Director of Agriculture 


* P \RT III. 

LEGISLATION RELATING TO LIVESTOCK, BEES AND 

WILD BIRDS. 

LIVESTOCK— GENERAL. 

Pounds Oidmanct No. 1 of 1868, (Cap 93) 

This Ordinance deals with the impounding of stray cattle and the regula- 
tions controlling it. 

Pound Fhh Puli s and Deputations, 1987. 

These Rules reduce by 50 per cent, the pound fees payable m respect of wild 
animals straying on private premises or land, but do not affect the impounding 
of stress on publio premises or land. 

Cattle Shalinp Previntnm Oidmana, No. 3 of 1877, ( Cap 94). 

This Ordinance deals with the branding oi Cattle and the regulations which 
control it, also with the movement of Cattle on the highways and the control 
thereof. It also enacts that the skin of any slaughtered Cattle shall be kept for 
a stipulated period for examination if required. 

Cattle Tiad (Tolls) Oidtiianoc, No. 16 of 1929. 

By this Ordinance the Governor-in-Council may make regulations prescrib- 
ing the payment of .tolls for the passage of Cattle over the Cattlt Trail. 



A SUMMARY OF AGRICULTURAL LEGISLATION IS BRITISH GUIANA. 261 

Free Importation op Cattle Foods. 

Department of Agriculture Notice No. 57 published in the “ Official Gazette ” of 

July 10, 1937. 

This notice states that under the Customs Duties, 1935, as amended by 
Section 4 of the Customs Duties (Amendment) Ordinance, No. 26 of 1936, the 
following cattle foods may be imported free of duty provided that their quality 
is approved by the Director of Agriculture, to wit : Soya Meal extracted, 
Linseed Cake, Dried Separated Milk, Meat and Bone Meal, Meat Meal, 
Fish Meal (white), well known proprietary Calf Meals, Barbados Cotton Seed 
Meal. 


VETERINARY, 

The Animals Diseases Ordinance, No, 29 of 1936. 

This Ordinance provides for the proper registration of all Veterinary 
Surgeons. It also states the conditions under which animals may be imported 
No animal may be imported without permission of an officer appointed by the 
Director of Agriculture, and any animal so imported, or suffering from disease 
on arrival, may be destroyed. When disease is suspected in any area of the 
Colony, the Govornor-in-Council may declare such an area to be an infected 
area and stipulations are made concerning the movements of stock or carcases 
into, out of or within such areas. Notification of disease must be given immedi- 
ately to the Police. Diseased animals may be slaughtered, for which the 
Governor-in Council may award compensation. Special provisions are made as 
to outbreaks of Anthrax, calling for the inoculation and marking of animals in 
tho aiea concerned. If Glanders or Farcy recur within two years in the same 
building, isolation of such building may be required by the Director of 
Agriculture, and by order ot the Governor-in-Council the Colonial Teasurer may 
recover the cost of isolation or disinfection from the owner of the premises 
concerned. It is tho duty of every Police Constable to enforce the Otdinance. 
Details are given as to what constitute offences under the Ordinance and the 
purposes for which the Governor-in-Council may make regulations. 

Under this Ordinance The Animals (Breed and Contagious Diseases) 
Ordinances, No. 5 ot 1920, (Cap. 272) and No. 38 of 1932 are repealed. 


Exportation op Animals. 

The Animals Diseases Regulations, 1937. 

These regulations require that no animal shall be exported before it is 
inspected by the Government Veterinary Surgeon, or a Veterinary Surgeon 
appointed by the Director of Agriculture and is certified to be free from disease 
and fit and suitably for export. A scale of fees for inspection is laid down. 



AGRICULTURAL JOURNAL Of faftlTISU GUiANA. [iX, 4. 

Importation op Animals. 

Order in Council No. 572 dated March 19, 1957 and published 
in the "Official Gazette” of April 24, 1937. 

This Order states the conditions nnder which importation can be made into 
the Colony of animals, carcases, fodder or litter from any of the following 
specified places, to wit: Great Britain, Ireland, Canada, the West Indian 
Islands, the United States, Brazil, the Argentine, French Guiana, Surinam 
and Venezuela. All animals and carcases from these places are to be accom- 
panied by a certificate signed by a Veterinary Surgeon on behalf of the 
Government Department of the country of origin certifying that they 
are free from disease, and in the case of cattle, that they have passed the 
tuberculin test. Fodder or litter must be accompanied by a certificate signed 
by a Veterinary Surgeon of the country of origin certifying that it is from a 
district free from disease. On arrival in the Colony animals must be certified 
as free from disease. 

BEES. 

f 

The Importation of flees Ordinance, No. 33 of 1935. 

This Ordinance permits the Governor-in-Council to make regulations for 
the purpose of regulating the importation of bees and beekeepers* stock. 

The Importation of Bees Begu/ations, 1930. 

These Regulations prohibit the importation into the Colony of (a) honey, 
combs ; (b) hives and other beekeepers’ stock which have been previously in 
use ; (c) queen bees ; (d) worker bees and drone bees in any stage of develop- 
ment exoept with the written permission of the Director of Agriculture. 
Stipulations are made in regard to the manner and quantity in which bees and 
queen bees may be imported. 

The Importation of Bees ( Amendment ) Ordinance, No. IS of 1986. 

By this Ordinance power is given the Director of Agriculture to destroy or 
cause to be destroyed any bees or bee equipment imported in contravention of 
regulations passed by the Governor-in-Council. 

PROTECTION OF WILD BIRDS. 

The Wild Birds Protection Ordinance, No. 31 of 1919, {Cap. 273) Amended 

by Ordinance No. 27 of 1934 and by Order in Council No. 701 
dated November 5, 1934 and published in the “ Official Gazette ” 
of November 10, 1934. 

This Ordinance schedules a large number of wild birds for absolute pro- 
tection, and a smaller number for protection during the close season, from April 
1, to August 1, excepting Ibises (Cari-Curi, etc.) for which the close season is 
January 1, to August 1. It is an offence to kill or injure, or capture or offer for 
sne any of the birds scheduled. An exception is made in the case of birds 
killed of necessity in the bosh for food, and of Pigeons in the neighbourhood of 
Rice fields, and Aboriginal Indians are not liable to conviction under the 
Ordinance* t 



REVIEWS. 


Cacao and Witch Broom Disease (Marasmus peraiciosus ) of South 
America.— With Notes on other species ofTheobroma. Report by Dr- F. J. 
Pound , Agronomist , Dept. o/Agric „ Trinidad, on a visit to Ecuador, the Amazon 
Valley and Colombia, April 1937 — April 1938. Pub, Turtle's Printerie, 06 
Marine Square, Port qf Spain, Trinidad. ( 58 pp.) 

The first part of Dr. Pound’s most interesting report deals with the varieties 
of cacao used for oommercial purposes and the search for types resistant to Witch 
Broom, In a short account of the history of Witch Broom Disease, he points 
out tho havoc played by tho disease and the difficulty of economic control with 
the falling price of oacao, the only practical methods of combating the damage 
being to improve yields and to discover resistant or immune varieties to replace 
those at present cultivated. In order to discover such varieties, it was realised 
that a thorough search must be made in the cacao growing countries of South 
America and Dr. Pound’s journey was the culmination of a good deal of prelim* 
inary work done with this end in view. 

The search for resistant varieties was finally carried to the Amazon Yalley, 
when it was realised that Ecuador and the Guianas were only outlying areas of 
this larger and more severely infected region. The types of cacao found in the 
varying tributaries of the Amazon Valley are described in some detail. 

In tho lower Amazon, trees were found which were apparently immune if 
isolated and exposed to bright sunlight, while in the Upper Amazon others were 
found which were highly resistant and probably immune even under such 
conditions as might be found on cacao plantations. 

The seoond part of the report concerns the non-commercial species of cacao 
which occur throughout the region traversed and concerning whiqh there is 
considerable confusion. Though all the species cannot yet be distinguished with 
certainty, a number of groups of similar types havo been defined, into which 
most of the known species can bo placed, though a few still remain which do not 
oonform to these. The difficulties of correct determination are largely due to 
lack of adequate material on which to base propor descriptions, and a multiplicity 
of local names has also added to the confusion. 

The third part of the report deals with the' method employed to make 
available for use in Trinidad the Witch Broom resistant varieties that were found. 
In order to avoid risk of introducing diseased material into Trinidad, seed was 
sent to Barbados and it is being grown there in quarantine, whence it will be 
possible to obtain budwood for propagation in Trinidad. The method employed 
to send the original seed to Barbados is of interest, To prevent fermentation 



864 


AGRICULTURAL JOURNAL 07 BRITISH GUIANA. 


[IX. 4. 


taking place en route, the mucilage was got rid of by kneading the seed in very 
dry sand, the mucilage-soaked sand then being removed by hand, after which 
the seeds were packed in fresh powdered wood charcoal, slightly moist. 

E. B. M. 

The Principles of Cane Sugar Manufacture By J. 6. Davies. Pub. 
Norman Rodger , London. 10\-. ( 140 pp„ 24 plates, 17 figures). 

This book will be very useful to those who are interested in sugar manu- 
facture “ amongst other things. ” Whilst we agree that the cobbler should 
stick to his last, we sometimes wish that we could drop in on him and talk 
cobbling knowingly though superficially. But we cannot forget our first visit 
to a sugar factory, when an overstrained voice shouted unintelligible explanations 
in competition with the death -cries of a phalanx of noble canes. 

The book was obviously written for sugar estate overseers who wish to 
know what happens after their canes disappear up the cane-carrier, but it will 
also appeal to many who have to scrutinize factory reports without a very clear 
idea of what it all means. Some sugar technologists may sneer at it — comparing 
it with Noel Deerr, Pi insen Geerligs, Browne and Tromp — but it may make them 
more readily understood when they “talk shop”, and they will be able to avoid 
theawkward task of explaining pH by referring their more inquisitive friends to 
page 31. 

To give an outline of sugar manufacture in 140 pages is an achievement, 
and the numerous plates and diagrams permit a nodding acquaintanceship 
which may be developed at leisure into a better understanding. 


D. W D. 



NEWS. 


The Department takes this opportunity of congratulating Capt. F. Barnett. 
MX*., M.A., on his promotion as Commissioner for Land Settlement in Jamaica, 
Capt. Barnett was appointed Depnty Director of Agriculture in British Guiana 
in 1929. The district agricultural work was under his immediate supervision 
and he rendered valuable assistance in connection with the working of the pure 
line padi improvement scheme. He also gave a great deal of his time to co-opera- 
tive schemes in relation to rice marketing and to land settlement problems. 
He acted on several occasions as Director of Agriculture and as a member of the 
Legislative Council. He takes with him the good wishes of his colleagues for 
success in his new appointment. 


Consequent on the promotion of Mr. J. D. Gillespie, B.Kc., to be Agricultural 
Officer, Sierra Leone, the Secretary of State for the Colonies has been pleased to 
appoint Mr. T. Bell, n.s.A. (Hons.), (Toronto), A.l.o.T.A., to be Agricultural 
Superintendent in British Guiana. Mr. Bell was the Assistant Manager of the 
Government Stock Farm and Agricultural Station in Palestine andartivedin 
the Colony oo December l:i. 


Consequent on the promotion of Mr. H. A. Cole to the Senior Grade, His 
Excellency the Governor has been pleased to appoint Mr. 0. F. J. Churaman, 
Dip. Agr., to be an Agricultural Instructor as from August 24, 193t>. 


Mr. L. D. Cleare, F.lt. Eat. a., Entomologist, returned from leave of absence 
on October 21. While on leave Mr. Cleare attended the seventh International 
Entomological Congress held in Berlin from August 14 to 21. 


The Department offers its congratulations to Mr, H. D. Huggins, M.sc., Dip. 
Agr., Agricultural Superintendent, on the occasion of his marriage on Novem- 
ber 1. 

Mr. W. G. Delph, Registrar of Banks, left the Colony on six months’ 
leave of absence on December 5. Inconsequence, Mr, A. A. Thorne, Account- 
ant, has been appointed to act as Registrar of Banks and Mr. C. A. LaBhley of the 
Treasury Department a3 Accountant. 

Mr. H. Parker, General Manager of Government Rice Mills iivthe Federated 
Malay States, who was detailed to investigate the possibility of erecting 
Central Rioe Mills in British Guiana, particularly in Essequibo, and generally to 



266 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [IX, 4, 

consider rice milling problems in the Colony, left on Ootober 23, his visit having 
lasted rather over a month. Daring his stay in the Colony, Mr. Parker made 
several visits to rice-growing districts, where he inspected the rice mills and dis- 
cussed the problems with persons engaged in the industry. He met the 
Esseqnibo Coast Committee on several oeoasions. It is hoped that his report will 
enable a step forward to be made in the milling end of the industry. 


Among the visitors to the Department have been Major G. St. J. Orde 
Browne, O.B.E., Labour Adviser to the Colonial Office and his Secretary, Mr. R. 
Norris. 


The first quarterly meeting of the B.G. Poultry Association was held at the 
Department of Agriculture on October 24, a large number of members being 
present. The President gave an interesting address on the “ Production and Care 
of Eggs ” which was much appreciated. 



LEGISLATION 


Legislation has recently been enacted prohibiting the importation of nee 
seed (padi) under Section 3 of the Plant Diseases and Pests (Prevention) Ordin- 
ance, 1935. 


An Order in Council under Subsection (3) of Section 4 of the Sugar Quota 
Ordinance, 1937, has recently been passed allocating the quota for the year 1st 
September, 1938 to 31st August. 1939. The allocations are as follows : 


Factory 

Manufacturer 

Allocation 
in tons. 

Albion 

The Corentyne Sugar Company Limited 

13,195 

Blairmont 

S. Davson & Company, Limited 

15,184 

Cane Grove 

Bookers’ Demerara Sugar Estates, Limited 

4,221 

Diamond 

The Demerara Company, Lmited 

23,600 

Enmore 

The Enmore Estates, Limited 

10,771 

Friends A. Mara 

The New Friends, Limited 

500 

Houston 

Plantation Houston Sugar Estates Company, 
Limited 

1,799 

La Bonne Intention 

The Ressouvenir Estates, Limited 

9,914 

Leonora 

The Demerara Company, Limited 

10,400 

Lusignan 

The Enmore Estates, Limited 

10,398 

Ogle 

The Ogle Company, Limited 

4,408 

Port Mourant 

Port Mourant, Limited 

13.630 

Rosehall 

Bookers’ Demerara Sugar Estates, Limited 

14,698 

Ruimvelt 

The Demerara Company, Limited 

1,600 

Skeldori 

Bookers’ Demerara Sugar Estates, Limited 

10,643 

Uitvlugt 

Bookers’ Demerara Sugar Estates, Limited 

11,937 

Versailles & 

Schoon Ord. 

Plantation Versailles and Schoon Ord, 

Estates, Limited 

4,408 

Wales 

West Bank Estates, Limited 

5,374 



PLANT AND SEED IMPORTATION. 

Introductions by the Department of Agriculture for the period 
September — November, 1938. 


Name 

Quantity. 1 

Whence Supplied 

Economic . 


1 


Vegetable Seed, 13 varieties 

2 

lb. 

Sutton & Sons (Calcutta). 

Vegetable Seed, Assorted 1 

4 

lb., 14 oz. 

Sutton & Sons, Reading, 
England, 

Onion Seed, 2 virieties 

28 

lb. 

Hamilton & Co., Teneriffe. 

A^cado Pears, Guat email variety 1 

i 

G 

seeds 

Director of Agriculture. 
Mauiituis, 

Rexoro Padi 

I 

20 

lb. 

Dr. G. Stahel, Agr). Expt. Stn , 
Paramaribo. 

Lettuce, 4 varieties 1 

1 

oz each 

Ferry ‘Morse Seed, Co., 
California. 

( 

Ornamental. 




Hyphaene conacea , M.ut 1 

8 

seeds 

Royal Bot. Gardens, Kew. 

„ parvula 

18 

seeds 

do. 

Piggftetia elata 

; 44 

l 

seedlings 

Coconut Grove, Palmetum, 
Florida 

Coopei ia pechnmihita 

i 

5 

bulbs 

American Amaryllis Society, 
Flonda. 

Crmum ameriramim 

i 

G 

bulbs 

do 

Ldium cat < shun 

18 

bulbs 

do. 

Zephymnlhe atama^ro 

3 

bull>s 

do 

,, pulch'tla 

3 

i 

bulbs 


„ t) (attar 

1 1 

bulb 


Hibiscus, 18 varieties 

i 12G 

i 

cuttings 

Impen.il College of Tropical 
Agriculture, Trinidad. 

PUcairvia rectn rata 

1 packet j 

Da\id Barry & Co., California. 

„ Alternttmu Lem. 

i 

do. 

do. 

Guzmania species 

i 

i 

do. 

do. 

Flower Seeds, Assorted 

i 

4 

lb., 3 oz. 

Hurst <£ Sons, London. 


1 & 9 

pkts. 







METEOROLOGICAL DATA-JULY TO SEPTEMBER, 1938. 


fieoording Stations & 
Months. 

Rain- 

fall. 

NUMBER OF DAYS OF RAIN 

Botanic Gardens. 

Total 

Inches. 

n 

if 

a 

P 

10 to 
| 50 Ineh 

•50 to 

1.00 Inch 

5 5 

« fi s>! 

* 8 «S 

e» ) w 

Total days 

July 

1274 

7 

8 

4 

1 

2 

22 

August 

14 96 

6 

7 

4 

3 

2 

22 

September 

1-85 

3 

3 

i 

... 

... 

7 

Totals 


16 

18 

9 

4 

4 

51 

Means 

... 

... 

... 

... 

... 

... 

... 

Berbice Gardens. 



1 





July 

933 

6 

4 

4 

2 

1 

17 

August 

12.63 

1 

n 

4 

5 

... 

21 

September 

.57 

4 

2 

... 

... 

... 

6 

Totals 

22 53 

11 

17 

8 

7 

1 

44 

i 

Means 

... 

... 

... 

... 

... 


... 

Onderneeming. 


i 






July 

10.41 

1 ••• 

I 11 

1 5 

3 

I 

... 

19 

August 


5 

i 

11 

i ^ 


... IS 

j . 

September ... 5-59 

! ^ 

5 

I 

1 1 

| I ] 

i 

9 

Totals 

20-17 

6 

1 

27 

1 8 

4 

i 

1 

46 


Evapo- 

ration 


Inches 


Air Temperature 
and Humidity. 


I 


la 

ts 


85-1 74-9 80-0 88-6 


1 86-3 


75-0 


80-6 83-.J 


5-00 , 8S-2‘ 75^i 82. 5 80-1 


1 13-58 


Means 


I 86 .) 75.6 81-0 824 


88-0 74.9 81.4 78.6 
89.7 74-9' 82 3 80-7 
i 91*1 76.6 83.8175.7 


89.6 75-5 82 5> 78-3 


I ! 

85.0, 72.4 
87-2, 73.5 


88-4| 


74. 5j 


78.7 92.8 

i 

80-1,92.6 
81. lj 90.9 


86-9 73-5 80.1: 


Hosororo, 

North West District I 
July ...J 

8-04 

1 

u ! 

11 

4 

i 

l 

1 

! 

! _ I 

i 

27 


August ...j 

17-20 

4 ! 

8 : 

10 

4 

i 

27 

... 

September ...j 

4-57 

9 | 11 

3 

) 

... 

... i 

23 

... 

Totals • 

29-81 

24 30 

17 

5 

i 1 

77 

... 

Means 

... 

... | ... 

{ 

|... 

... 

... 

I 

1 


86. 5| 69-9 


78-2! 


92-1 


87-8 


70.*5| 88.4' 79-4 89-0 
70-6| 89-6{ 80.1 87.5 


j 75-9 


82-6 


79.2 88-1 



CURRENT PRICES OP COLONIAL PRODUCE 


From The Commercial Review, Journal of the Georgetown Chamber 
of Commerce, Vol. XXI, No. 11, Wednesday, 30th November, 1938 . 

SUGAR. 

Per 100 lb. net 3 lb. per Bag allowed for tare 


Dark Crystals for Local Consumption... 13.30 

Yellow Crystals do. do $4.00 

White Crystals $4.75 

Molasses Sngar none offering. 


Above Prices include Excise Tax of 90c. 

RUM. 

Imperial Gallon. Cask included. 

Coloured, in Puncheons — 40 to 42 O.P...(for export). ..60c.; Hhds. 52c., Barrels 77c* 


White, in Hogsheads — 40 to 4.) O.P...(for local consumption) 45 to 55c. 

MOLASSES. 

Per Imperial Gallon. Naked. 

Yellow (firsts) 10c. 

Yellow (seconds) 5$c. 


RICE. 

Rice per Bag of 180 lb. gross. Brown Super $3.60 — $3.75 ; Extra No. 1, 

$3.00 — $3.25 ; White, None available. Lower Grades $2.25 — $2.50 as to quality, 
Padi..,., ....per Bag of 143 lb. gross, $1.20 — $1,50 as to quality. 


GENERAL. 

Gold, Raw average per oz. $27 to $28. 

Diamonds, — pro rata as to quality average per carat $10 to $11. 

Timber, Greenheart, (Lower grade measurements)... 40c. to 60c. per c. ft. ; 

for export 72c. to $1.00 per c. ft. 

do. Railroad Sleepers — (Mora) $1 .68 each. 

Greenheart Lumber $70 to $80 per 1,000 feet. 

Crabwood Lumber $60 to $75 per 1,000 feet. 

Shingles, Wallaba, 4 x 20 and 5 x 22 inches, $4.50 to $6.00 per M. 

Charcoal, Capped for shipment 72c. to 85c. per bag. 

Firewood $2.50 per ton. 

Coconnts...Selects, $9.00, culls $6.00 per M... Copra $2.00 per 100 lbs. prime Copra. 

Balata... Venezuelan, none. Local Sheet.. .36c. to 38c. per lb. 

Cocoa.I.. 19c. to 19ic. „ „ 

Coffee 8c. to 9c. „ „ 


N.B.— Duty Payable on value at tune of Importation and rate of exchange on day of 
arrival. 



INDEX TO YOL. 1A. 

1938 

A 

Page 

Agriculture — Fifteenth Meeting of Advisory Board of ... ... 178—182 

Agricultural Legislation in British Gniana and the 

Caribbean Colonies ... ... ... ... 25 — 38 

Agricnltnral Legislation in British Gniana — Summary of ... 24 (i — 262 

Amazon Fly in British Gniana, 1937— Status of the ... ... 12 — 24 

Appointment of Bell. T. as Agricultural Superintendent ... 265 

„ Churaman, 0. F. .T. as Agricultural Instructor ... 265 

„ ,. Fraser, H. A. to act as Government Veterinary 

Surgeon ... ... ... ... 127 

,. „ Williams, C. H. B. as Sugar Agronomist 

and Plant Breeder ... ... ... ... 67 

B 

Bees — Summary of Legislation in British Guiana ... ... 262 

Beekeepers* Association— Minutes of the Fifteenth Meeting 

of the British Gniana ... ... ••• 64 — 66 

Beetles — Damage caused to Bum Puncheons by Boring ... 237 — 245 

Bell, T.— Appointment of, as Agricultural Superintendent ... 265 

Board of Agriculture — Fifteenth Meeting of the Advisory ... 178 — 182 

Bone, T.— Retirement of, as Government Veterinary Surgeon ... 127 

Boron in Agriculture ... ... ••• ••• ^7 — 119 

Botanic Garden — The Georgetown : Some Notes on 

its Early History ... ••• ••• ••• 207— 216 

Bourne, C. L. C. — “A Milling Test on Sixty Padi Varieties” ... 163—168 

British West Indies Fruit and Vegetable Council ... ... 190 — 125 

Bronze-Leaf Wilt Disease of the Coconut Palm ... ... 54 — 57 

Burnett, F.— “Results of Padi Varietal Trials and Extension 

Work. 1937” ... ... - - 82-100 

„ „ —Promotion of, to be Commissioner for Land 

Settlement, Jamaica ••• ... ••• 265 

P 

Cacao and Witchbroom Disease of South America ... ... 263—264 

Cameron, C. — “ The Boring Points for Refractometer Tests 
of Sugar Cane” 


• •• 


47—50 



iv 


Index to Vol. IX. 


Dane in British Guiana— A Water Rat Damaging 

.. — The Boring Points for Refractometer Tests of ... 

Case, G. 0. — “The Use of Vegetation for Coast Protection” 
Child, R. — “Edible Coconut Oil” 

Chitraman, 0. F. J. — Appointment of, as Agricultural Instructor 
Citrus fruit — Legislation prohibiting the importation of from 
the British West Indies 
Clarification of Sugar Syrups ... ... 

Clears, L. D — “A Water Rat Damaging Sugar Cane in 
British Guiana ” 

«. — “ Damage Caused to Rum Pancheons by 

Boring Beetles” 

» .. — “Plant Legislation in British Gniana and the 

Caribbean Colonies” ... <.. 

.. — “Status of the Amazon Fly in British Guiana, 1937 

Coconut Oil— Edible 

., Palm — Bronze-Leaf Wilt Disease of the 
„ Wilt in Essequibo and Pomeroon Districts 
Coconuts — Summary of Legislation concerning, in British Guiana 
CofFee Quality 

Cole, H. A. — Promotion to the Senior Grade of 
Agricultural Instructors 

Credit— Summary of Legislation concerning, in British Gniana 


Page 

217—229 

47—50 

4-11 

109—116 

265 

120 

61—62 

217—229 

237- 245 

25 — 38 
12-24 
109-116 
54—57 
147—152 
254-255 
51—53 


Current Prices of Colonial Produce 


67 

... 256—257 
72. 131, 193, 270 


Dairy Heed, A Grade 

Dhal — Methods of Preparing Marketable 

Diatraen 

Dtjthie, D. W. — “ Coconut Wilt in Essequibo and 
Pomeroon Districts” 

•• •> - “ A Milling Test on Sixty Padi Varieties’ 


153—162 

169—177 

12—24 

147—152 

163-168 


E 

Edible Coconut Oil 
Editcgials : 

Economic Stock-Raising 
Pasture Grasses 
Rice-Situation 

llojal Commissions— Past and Present 


109-116 


133-134 

1-2 

73—74 

195—196 



Index to Vol. IX 


▼ 


Fertiliser and Variety Position of the Sugar Industry, IV ... 101— I0K 

Fraser, H. A. — “A Grade Dairy Herd” ... ... ... 153 — 102 

„ „ — Appointment of, to act as Government 

Veterinary Surgeon ... ... ... 127 

Fruit and Vegetable Council, British West Indies ... ... 120 — 125 

G 


GAYWAfiA, P. M. — “The Cultivation of the Pigeon Pea {CnjmiUH 

rtijaii) and the Methods of Preparing Marketable Dhal” ... 109 — i 77 

GlWjioi,!, G — “ Malaria in British Guiana,” I, LI, III, 75-81, 135- 140, 197 — 200 


OiULEsriK, J. D. — Promotion of ... ... ... 127 

Grasses — Presidential Address at the 4th International 

Grassland Congress ... ... ... ... 39—40 

I 

Importation of Plants, Legislation relating to the ... ... 25 — 38 

L 

Legislation— Allocation of Sugar Quota for year 1938— 39 ... 207 

., —Appointment of Plant Inspectors ... ... 02 

„ — Control of Sugar Experiment Stations ... ... 62 

—List of Registered Veterinary Surgeons ... ... 02 


,, in British Guiana and the Caribbean Colonies, Plant ... 25—38 

., „ „ — Summary of Agricultural ... 240—202 

„ force in the Caribbean Colonies relating to the 

importation of plants — Summary of ... ... 30 — 37 

„ prohibiting the importation of plants into Trinidad ... 120 

„ „ „ „ „ all citrus fruit from 

the B.W.I. ... ... 120 

„ „ ,. „ rice seed (padi) ... 207 

Livestock Importations ... ... ... ... 08 

„ Industry — A short History of the llupununi Savannahs with 

special reference to the ... ... 230 — 236 

„ — Summary of Legislation concerning, in British Gniana 200 — 202 

Lonchocarpii* sp. ... ... ... ... ... 57 

M 

Malaria in British Guiana, I, II, III ... 75—81, 135—146,197 — 2( 0 

Mangrove ... ... ... ... ... ... 4 — 11 

MarTYN, E.B. — “The Georgetown Botanic Garden: Some Notes 

on its Early History ” ... ... ... 207— 210 



vi 


Index to Vol. l£ 


Pag® 

Meteorological Data ... ... ... ... 70 — 71,130,192,269 

Milling Teat on Sixty Padi Varieties ... ... ... 163 — 168 

News ... ... ... ... 67—68.126—128, 190,265—266 


Notes : 

Boron in Agriculture ... ... ... ... 117 — 119 

British West Indies Fruit & Vegetable Council .. ... 120 — 125 

Bronze-Leaf Wilt Disease of the Coconut Palm ... ... 54 — 57 

Clarification of Sugar Syrups ... ... ... 61 — 62 

New ornamental Plants Introduced into the Botanic 

Garden during 1937 ... ... ... ... 119 — 120 

Padi & Rice Production in India and Burma ... ... 183 — 189 

Rotenone Yielding Plants of South America .., ... 57 

Soil EroBion ... ... ... ' . . ... 39 — 61 

Surinam and Curacao ... ... ... ... 58 — 59 


o 

Oil, Edible Coconut ... ... ... ... ... 109 — 116 

P 

Padi — A Milling Test on Sixty Varieties ... ... ... 163 — 168 

„ and Rice Production in India and Burma ... ... 183 — 189 

„ Varietal Trials and extension Work, 1937 — Results of ... 82 — 100 


Parker, H.— Visit of ... ... ... ... 190 

,, „ — Departure of ... ... ... ... 265 

Pigeon Pea (Cajanvs mjan) — The Cultivation of ... ... 169 — 177 

Plant — Legislation in British Guiana and the Caribbean Colonies ... 25 — 38 

„ & Seed Importation ... ... ... 69, 129, 191, 268 

Plants — Legislation prohibiting the importation of, into Trinidad ... 120 

Prices of Colonial Produce ... ... ... 72,131, 193,270 

Q 

Quota — Allocation for year 1938-39 of Sugar ... ... 267 

R 

Rat Damaging Sugar Cane in British Guiana — A Water ... ... 217 — 229 

Ref raffometer Tests of Sugar Cane — The Boring Points for ... 47 — 50 

Report : 

The Fifteenth Meeting of the Advisory Board of Agriculture 178 — 182 

Results of Padi Varietal Trials and Extension Work, 1937 • ... 82 — 100 



index to Vol. IX 


Reviews : 

Cacao and Witchbroom Disease of Sonth America... 
The Practical Aspects of Copra Deterioration 
The Principles of Cane Sugar Manufacture 
Rice — Average Prices of 

„ — Summary of Legislation concerning, in British Guiana 
„ and Padi Production in India and Burma 
Rotenone Yielding Plants in South America 
Rum Puncheons — Damage Caused to, by Boring Beetles 
Rupununi Savannahs — A Short History of the, with special 
reference to the Livestock Industry 


263—264 

63 

264 

73 

252—254 

183-189 

57 

237—245 

230—236 


Seed and Plant Importation ... ••• ... 69,129,191,268 

Selected Articles : 

Boring Points for Refractometer Tests of Sugar Cane 47 — 50 

Cultivation of Cajanus cajan and Methods of Pre- 

- paring Marketable Dhal ... ... .. 169 — 177 

Coffee Quality ... ... ... ... 51 — 53 

Edible Coconut Oil ... ... ... ... 109—116 

Presidential Address at the 4th International Grass- 
land Congress ... ... ... ... 39 — 47 

Soil Erosion ... ... ... ... ... 59 — 61 

Spartina Grass ... ... ... ... ••• 4 — 11 

Sugar — Allocation of Quota for year 1938-39 ... ... ... 267 

„ —Summary of Legislation concerning, in British Guiana ... 250—251 
„ Cane — The Boring Points for Refractometer Tests of ... 47—50 

„ „ in British Guiana — A Water Rat Damaging ... 217 — 229 

„ Industry — The Variety and Fertiliser Position of the, IV ...' 101 — 108 

„ Syrups, Clarification of ... ••• ••• ••• 61 — 62 

Statledon, R. G.— Presidential Address at the Fourth Inter- 
national Grassland Congress ... ••• 39 46 


TtJRNEA, H. E— “ A Short History of the Rupununi Savannahs 

with Special Reference to the Livestock Industry” r . 


230-236 


Use of Vegetation for Coast Protection— The 



Index to Vol. lit. 


viii 

V 

Varietal Trials and Extension Work in Padi, 1037 — Results of ... 82 — 100 
Vegetation for Coast Protection — The Use of ... .. ... 4—11 

w 

Water Rat Damaging Sugar Cane in British Guiana . ... 217 — 229 

Williams, C. H. B.— “The Variety and Fertiliser Position of 

the Sugar Industry, IV ” . ... 101 — 108 

., ,, - Appointment of, as Sugar Agronomist and 

Plant Breeder ... ... ... 67 

Wilt Disease of the Coconat Palm — Bronze-leal . . ... 34 — 57 

„ in Essequibo and Pomeroon Districts— Coconut .. ... 147 — 152T 



THE 


Agricultural Journal 

op 

British Guiana 



DEPARTMENT OF AGRICULTURE 
GEORGETOWN 
BRITISH GUfANA, 




Vol. X, No. i. 


March, 1939. 


The 

Agricultural Journal 

of 

British Guiana 



l5goq 

PUBLISHED BY 

THE DEPARTMENT OF AGRICULTURE, 

GEORGETOWN. BRITISH GUIANA 


Price 


• a 
aa 


aa 

aa 


6d. 




DEPARTMENT OF AGRICULTURE. 


Director of Agriculture 
Deputy Director 


ADMINISTRATION 

... ... Prof. The Hon. J. Sydney Dash, 

B.Sc. (Agric.) 

(vacant) 

L. D. Clcare, F.R, Ent. S. (acting) 

Clerical Staff. 


Senior Clerk 
Registrar of Banks 


Class III Clerks 


Probationers 


Librarian 

RESEARCH BRANCH. 

Botany and Plant Pathology 

Hotauiht— Plant Pathologist and Supei intend- 
cut. Botanic ( hardens : 

E. B. Martyn, B.A., A.l.C.T.A. 

Technical A Militant .* 

N. Persaud 

Chemistry 

C hr mint • 

D. W. Duthie, M.A . B.Sc., l’h.D . F.I.C. 

Assistant Chemist : 

C. L. C. Bourne 

Economics 

Agricultural Economist . 

H. 1). Huggins, M>c., Dip. Agr. 

Entomology 

Entomologist . 

L. l>. Clcaro. F.U. Eut. S. 

Technical Assistant : 

C. Williams 

Rice 

Assistant Plant Uriah r : 

P. A. Chan Choong, B.Sc., A.l.C.T.A. 

Sugar 

(In co-operation with the Sugar Producers) 

Sugar Agronomist and Plant Hradir: 

' C. H. B. Williams, M.A., A.l.C.T.A,, Dip. 
Agr. 

Labomtory Assistants : 

H. B. SingK 

A, V, Wan-Ping, Dip. Agr. 

Statistical Clerk ; 

J, B. Bourne 


J. F. Irving, M.C. 

/ W. G. Delph (on loa^ e) 
j A, A. Thorne (acting) 

] C. A. Lashley (acting) 

| Miss D. M. Terrill 

Miss M. Chcong 
P. O. Jackson 
, S. A. Adams 
Miss S. Lord 
^ Miss R. Delph 

Miss Y. Chan- Choong 


LIVESTOCK BRANCH 

Veter mart/ Surgeon : 

Vacant 

H A Fraser, B.Y Sc (acting) 

FIELD BRANCH 

Agricultural Superintendents : 

Berbice — A. A. Abraham 
Demerara, East — E. M. IVterkin 
Demcrara. East Bank— H. D. Huggins, 
M.Sc., Dip. Agr. 

Demerara. West — E. G. Benson, B.Sc., 
A.l.C.T.A., Dip. Agr. 
Esseijtiibo— T. Bell, B.S.A., A.l.C.T.A. 

Assistant Agricultural Superintendent : 

Berbice— E. M. Morgan 
Agricultural Instructors : 

Berbice— O. F. J. Churam.m, Dip. Agr. 
Botanic Gardens — H. A. < ole 
Demerara, East — C. C. Dowding, F.L S. 
F.R.H.S. 

Demerara, East Bank— I. Dewar (acting) 

Agricultural Assistants: 

Demerara, East — J. lndrobeharry 
Esscquibo — H, B. France 

Ter finical . A ssi.sfants ; 

Demerara, East — W. A. Bovell 

Essemiibo— A. W. Sears 

North West District— L? E. McKinnon 

Sugar 

Fit Id Manager (Central Station) 

C. Cameron 

Field Assistants : 

L. A. Forte 
B. A. McArthur 



METEOROLOGICAL BRANCH 

Technical Assistant : 

D. D. Blackman 

Meteorological Assistant : 

J. E. Isaacs 


RICE GRADING BRANCH 

Grading Inspector : 

H. E. H. Gadd 

Technical Assistants : 

R. H. Ross 
G. L. Leitcli 


ADVISORY BOARD OF AGRICULTURE 


Director of Agriculture, Chairman, ex officio. 

Deputy Director of Agriculture, Vice-Chairman, ex officio. 
Hon. Peer Bacchus ... ... ... \ 

Hon. R. E. Brassington ... ... ... I 

Hon. J. W. Jackson ... ... ... j 

Hon. F. J. Seaford, o. ile. ... ... ... > 

Mr. S. Andries ... ... ... ... ( 

" R. B. Hunter ... ... ... ) 

„ W. H. Richards ... ... / 


Members 


SUGAR EXPERIMENT STATIONS COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 
Hon. M. B (>, Austin, o.iu:. 

Mr, G. M, Kcclee 
„ J. C. Gibson 
t , A. Murison 

„ L. Lywood (acting for Mr. R. E. Rhodes) 
„ J. Bee 


Georgetown 
Pin. Biainnonf 
Pin, Port Mour.int 
Pin. Uitvlugt. 

Pin. Leonora 
Pin. Albion 


( Representing 
the Sugar 
Industry 
/ which main- 
I tains the 
' Stations 


COOPERATIVE CREDIT 

Director of Agriculture, Chairman, cx-nffirio. 

Hon. J. \V. Jackson 
Rev. A. K. Dyett ... 

Mr, C. Farnum ... 

„ J. L. Wills ... 


BANKS’ BOARD. 

\ Members 


DISTRICT AGRICULTURAL COMMITTEES 


EAST DEMERARA 

Director of Agriculture, Chairman 
District Commissioner 
Deputy Director of Agriculture 
Hon. J. I. dc Aguiar 
Hon. E. M. Walcott 
Mr. S. Andries ... 

,, M. Ghani 
,, W. H. Richards 
n J.E. Wills ... 



Members 


Director of Agriculture, Chairman 
District Commissioner 
Deputy Director of Agriculture 
Hon. J. W, Jackson 
Dn the Hon. J. B, Singh 
Mr. R. P. Carryl 
„ J. C. DaSilva 
R. B. Hunter ' 

„ A. Mhrison ... 
m W, Ramdeholl 
♦, A. Rayman ... 


WEST DEMERARA 

1 

j 


Members 


CONTENTS 

(Vol. X, No. 1.) 


PAGE 

EDITORIAL— 1 

ORIGINAL ARTICLES. 

Malaria in British Guiana, 

Parts IV. and V. ... ... <7. <hgholt, M.Ih (If.), .1/ (hmd.), 

D.T.M. ,(• II. (Eng.) ... ... 4 

Results of Padi Variety ‘ 


Trials, 1 ( .K38 

. I\ A . Cltan-Choon</> 

It. Sr., A.I.C.T.A. 

13 

Results of Recent Experi- 
ments with Sugar Cane 

. C. II . />’. 

Dip., 

Williams* 
Aijr . 

M.A., A.I.C.T.A., 

21 

Catalogue oJ the Lr/n<iupf< ra 
rJtup t I wont (Butterllies) 

of British Cuiami 

. 1 . nun. 

FJI. Knf . 

S. ... 

23 

NEWS 

, 


... 

12 

PLANT AND SEED IMPORTATION 

... 

... 

44 

METEOROLOGICAL DATA 




i:» 


ILLUSTRATIONS 




Ftrixc Pvge 

Plate 

L — Pig- 

1 — Distribution of Malaria along the Guiana 
coast between the estuaries of the Esse- 
quiboand Corentyne Rivers. The average 
rainfall at various points along the coabt 
is also shown ... ... ... f> 

Plati. 

, TI. -Fig. 

2 — The trend of the rainfall and malaria 
incidence curves as registered at Mac- 
kenzie on the Demerara River, in 192t> ... 7 

Plate 

III.— Fig. 

3 — The average (1908 — 1930) and the 1937 — ^ 

1938 rainfall, along with the number of 

cases of malaria recorded up to June 1938 ... 8 

Plate 

IV.— Fig. 

• 

1 — Rainfall and malaria on Bath Estate. 

1937—1938 ... ... ... 9 



Contents— Continued. 


Facing Pagb 

Plate V. — Diagram V. — Trend of the crude Vital Index 

on a group of live estates aggregating 
a population of 20,1167 which are free 
from endemic malaria ... 10 

Plate VI.— Diagram VI.— Crude Vital Index curve, 11*20 — 

1037 from a group of 10 Sugar Estates, 
aggregating a population of 20,832, which 
are subject to endemic malaria (spleen rate 
from f> to 30%) ... ... ... 11 

Plate VII.— Diagram VII. — Crude Vital Index curve, 1020 — 

1030, from a group of 7 Sugar Estates, 
aggregating a population, of 13,876, which 
are subject to severe endemic malaria 
(spleen rate 30 to 60%) ... ... 12 

Pl\TE VIII.— Pig. 1 - Xuptvgt'nes hymn (lorim. Female ... 26 

„ „ —Fig. 2 — Crrahrun mutilln <vnne,nt subsp. nov. 

Female (Type) ... ... ... 26 

„ „ —Fig. 3 — Psendosrnda wuua Hull. Male (Type) ... 26 

,, ,, — Fig. 1 — lMnumus heoalr ctcnret Hall. Male ... 26 

„ — Fig. •) — Vatayrammn Idas MtilL Female Underside ... 26 

„ — Fig. 6 — Pyrrhoijyru stmlonnus Fruhst. Female ... 26 

M „ —Fig. 7— Anna pithyma morena Hall. Female ... 26 

„ „ — Fig. 8 — Anlirrfuru tayyeUnn rodwayi subsp. nov. 

Female (Type). ... ... ... 26 

„ „ — Fig, 0 — Dtsniorpkia rrisiu rontunw subsp. nov. 

(Type) ... ... ... ... 26 

(All figures slightly reduced). 



Guiana. 


The 

Agricultural Journal of British 

March, 1939. 

EDITORIAL. 

RICE DEVELOPMENT. 

It is seldom easy to persuade a large number of individuals to follow a 
common course ; it is seldom easy even to get them to agree that a common 
course is worth following. It is no easier when many of those concerned are 
farmers who, as a class, have never easily sunk their individualities : win n, in 
addition, there are conflicting interests, the task is definitely hard. A case in 
point is the local rice industry which lias found it difficult to organise itself 
into effective business unics for purposes such as milling or marketing. 
Organisation for these ends has been elusive whether attempted by anybody 
within or without the industry. 

In the economy of the Colony, rice is second in impoitance to sugar. 
In most areas, rice, where now grown, has followed second on empoldered areas 
where sugar was first established. In all areas where both crops are 
grown, rice is second in importance in providing employment and meeting the 
charges for essential sen ices ; sugar is first. Xor are these the limits of this 
association. In those areas where the two crops exist together, the problems 
of rice cause only that amount of concern in the vicinities affected which the 
troubles of a secondary industry may be expected to arouse. This is the ca6e, 
generally speaking, in East Demerara, West Demerara and on the Corentyne ; 
on the other hand, where rice exists without sugar, the situation is different — 
especially in a district such as Essequiho which formerly knew the production 
of both crops and where sugar, once the mainstay, for one reason or another, 
goes out of cultivation. Rice is called on there to bear the responsibility in 
full which formerly it did in part in maintaining the standard of living of the 
community ; in such circumstance, the public hears a good deal of the troubles 
of rice. 

In 1910 there were on the Essequiho ('oust 0,471 acres under cane ; in 
1920 tips had fallen to 5,130 acres, in 1931 to 890 acies and in 1930 the last 
sugar estate, Hampton Court, ceased grinding. In the meanwhile, sugar had 
disappeared not only from the Coast, but from the whole Essequiho area, for the 
only other grinding factory — Pin. Marionville on the island of Wakena&m — had 
gone out of operation in 1930. It was clear that the new situation was having 
a far-reaching effect on those persons living and having financial interests in 
Essequiho, and Government appointed a Commission in 1934 to make recommen- 
dation as to what should best be done. As rice prices had fallen to uneconomic 



2 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [X, 1. 

levels, the project to which the Commission gave most thought was the keeping 
alive of the sugar industry in the area but, for financial reasons, Government 
found it impossible to take this course. 

The position in the meanwhile grew worse ; sugar production was restricted 
and it became difficult for labour from Esseqnibo to obtain enough seasonal 
employment on sugar estates in other districts of the Colony. 

With the pressing necessity for rice to give the highest possible returns to 
the cultivator, it seemed desirable that the industry’s major problem, milling, 
be tackled. Thus, last year, a committee was appointed to go into the “feasibil- 
ity of establishing at Anna Regina or some other central position a central rice 
mill.” Shortly after tin* committee began investigations, the Secretary of State 
for the (/(/lonies arranged for Mr. H. Parker, General Manager of the Government 
Rice Mill, Perak, Federated Malay States, to visit British Guiana to advise on 
the problems associated with changing over from small scale to large scale 
milling and to make recommendations with regard to the industry generally. 
Mr. Parker’s report has recently been published as lihs been the committee’s 
report as Sessional Papers Nos. 3 and 4 of 1939 respectively. 

Mr. Parker leaves no doubt as to w hat his findings are. He expresses 
himself emphatically. The pad i grown in British Guiana, he considers “of 
excellent quality-far superior to that of Malaya,” but of milling the view is 
different . “The major complaint of the psidi cultivator is that he cannot make 
sufficient profit by its cnlti\ation. Unfortunately all the inefficiencies in 
handling, milling and marketing tend to reduce that profit. The only solution 
is for the Government to erect a central mill”. Some of the advantages which 
he points out will result from central milling are : — 

(1) Reduction of overhead charges ; 

(2) Reduction in fuel costs as construction of boilers will permit 
burning of padi-husk ; 

(3) Uniformity in milling : 

(4) Recovery of by-products : 

(3) Storage oi parboiled padi resulting in controlled output of rice ; 
forward contracts could then be made ; 

(t!) Reduction in costs of articles such as bags, etc, which could be 
bought in wholesale quantities. 

(7) Low marketing costs effected bj single selling. 

• 

The Essoquiho Coast liico Committee's report, like Mr. Parker’s, strongly 
advises the erection of a central mill in Essequibo, the Committee’s report dis- 
easing in more detail the domestic problems that will arise. Some of the chief 
recommendations in the Committee’s report are : — 

£1) That Government provide fands in the form of a free grant for the 
erection and working capital of a central mill. 



fcfcltORtAL. 3 

(2) That, in the area covered by the central mill, the operation of 
other mills be prohibited. 

(3) That compensation be granted to proprietors of mills which are 
put out of operation. 

(4) That the price of padi be fixed by the central mill at the com- 
mencement of each crop, 

(5) That the mill make crop advances to land-owners on the basis of 
contracts for the supply of padi. 

(6) That the central mill itself dispose of its rice for export and for 
domestic consumption. 

(7) That Government grant loans to certain land-owner millers in 
Essequibo to enable them to pay off their indebtedness to merchant 
creditors in Georgetown. 

The Committee makes it clear that after experience has been gained in 
Essequibo with a central mill, others will and should follow in the several rice 
producing areas. With the advent of central milling and the more efficient 
control of the business end of the industry, the future of the Colony’s rice 
industry is thought to be more promising than at any time previously. It would 
appear that the Essequibo Coast Rice Committee and Mr. Parker have reasoned 
together with credit to themselves and advantage to an industry which though 
second in importance to the Colony as a whole is of first and vital importance to 
Essequibo. 


BERBICE AGRICULTURAL EXHIBITION. * 

Arrangements are now well in hand for the County Agricultural Exhibition 
which is to held in tho Colony House grounds, New Amsterdam, Berbice on 
Friday, April 11. The success of the effort must depend to a very large extent 
on the actiye help given by the agricultural community, but the Exhibition, being 
a County Show, must largely lely for its support on Berbice. 

Efforts have been made to ensure that farmers in all areas are acquainted 
with the date, tho object of the Exhibition and the methods of preparing products 
for exhibition. No entrance fee will be charged for exhibits and transport 
facilities are being arranged which, it is hoped, will enable exhibitors to transport 
their products with the minimum of trouble and expense. 



ORIGINAL ARTICLES 


MALARIA IN BRITISH GUIANA. 

BY 

G. GIGLIOLI, m.d. (It.) M.B c.P. (Loud.), D.T.M & H. (Eng.) 

Medical Adviser to the Sugar Estates of British Guiana. 

Pakt IV. THE DISTRIBUTION OF MALARIA ON THE COASTLANDS. 
GENESIS OF MALARIAL EPIDEMICS. 


In the previous sections, the life history of A . darling! , the local malarial 
vector, has been studied and the existence of certain factors ascertained, which 
tend to limit the distribution of this species and its seasonal incidence. Some 
of these factors, as water and soil salinity and acidity, influence this mosquito in 
its developmental stages, and thus limit the extent of its breeding areas ; others, 
such as atmospheric humidity and air movement, act directly on the adult 
insect and tend to influence its range of flight and its survival. 

We have attributed the uneven distribution of malaria throughout the 
Colony to variations in these factors. High soil and water salinity or acidity, 
atmospheric dryness and active air movement are all factors which are inimical 
to A . darling L Conversely, soils and surface waters of low salinity and only 
slightly acid, or neutral in reaction, offer suitable breeding sites ; a humid and 
quiet atmosphere will allow the adults of this species to fly over a much wider 
range and will favour their survival for a longer period. 

On the West Coast of Demerara the land is sufficiently high to allow 
natural drainage by gravity. The salt soil belt is very narrow and the cane 
cultivation and rice beds, with their net of irrigation canals, extend right up 
to the public road ; high coarida {Awcennia nitida) and other bush, and the 
thick groves of coconut palms, mangoes and other fruit trees which mark the 
nearly continuous ribbon-like village which extends for many miles along the 
public road, form efficient wind barriers. A. darling i finds suitable breeding 
and living conditions right up to the sea wall and malaria is more or less highly 
endemic throughout this whole coastal section. 

On the East Coast of Demerara the land is low T er, and natural drainage by 
gravity is not possible ; surplus surface waters must be disposed of by pumping. 
The front land soils are salt and their surface waters brackish. For this reason 
th^ge lands are mostly uncultivated and used only for pasturage* 

At Ogle the salt front lands extend for approximately 1 mile south of the 
sea wall ; this belt tends to become broader proceeding eastwards along the 
Coast 



Malabia I» BBltflSfi gttiaXa. S 

% 

The malaria rate, which is high on the estates situated nearer Georgetown, 
tends to fall progressively as the salt belt gets wider, and a larger proportion 
of the estate population resides in the salt front pastures. (Lnsignan, Enmore, 
Non Pareil). 

On the West Coast of Berbice the land is low, and the sea defences less 
efficient ; sea water in many points invades lands situated south of the public 
road and railway. These are the healthiest coastal localities west of the Berbice 
Estuary (Lichfield, Bush Lot, Hopetown). 

At Bath, the only sngar estate on this section of the coast, between 1934 
and 1937, the spleen rate averaged only 8.6, and in 1937 it was as low aB 1.5%. 

On the Corentyne Coast, as an average, the climate is drier ; the locality is 
notorious for its constant and high breeze. The width of the salt belt runs into 
miles ; the rice fields lying south of the public road are salt and windswept ; 
tree vegetation is very scanty and poor. At Albion and Skeldon the cane 
cultivation borders on the yards ; at Port Mourant nearly 3 miles of rice lands 
separate the cane cultivation from the estate village. The Corentyne Coast is 
usually free from endemic malaria. 

Diagram No. 1 shows the distribution of malaria, as indicated by the spleen 
rate, throughout the Guiana Coast — between the Essequibo and Corentyne 
estuaries — at the end of 1937 ; the tendency of the rate to fall progressively 
from west to east is well shown. The average rainfall also shows a Bimilar 
tendency, there being a difference of no less than 33 inches between the West 
Coast of Demerara and the Corentyne. No data are available as regards atmos- 
pheric humidity and air velocity for a comparative study of these factors 
throughout the coast ; the meteorological observatories of Georgetown and New 
Amsterdam are both situated on river estuaries. From general experience we 
believe it is safe to assume that the Corentyne coast is both drier and windier. 

It is usually believed in the Colony that the right bank of the river 
estuaries (Demerara and Berbice) is healthier than the left, and our findings 
tend to confirm this belief to some extent. On the estuaries, in general, con- 
ditions appear to be more favourable than on the coast for the breeding of 
.4. darling i , as the land is relatively higher and less salt, the cane cultivation 
extending nearly to the river banks. The night atmosphere is also damper, and 
morning mists are frequent ; malaria tends to be highly endemic. 

Diamond Estate — on the right bank of the Demerara River, some 11 miles 
from its ' mouth — and, to some extent, the village areas situated to the sonth of 
this plantation form a very notable and interesting exception which we are at 
present investigating. 

The distribution and incidence of malaria throughout the edast, as shown 
in diagram 1, can be accepted as what usually obtains under average conditions, 
but, occasionally, at intervals of 10 or more years, with a general exacerbation 
of malaria throughout the Colony, severe epidemic outbreaks occur also in 



6 AG&tCultfTJRAL JOtmNAL 6 $ fiEIttSfl OtTUtfA (X 1. 

localities whioh are usually free from the disease) notably on the Oorentyne 
Coast. Similar outbreaks were observed in 1926 and 1938 : both these epidemics 
we ascribe to abnormal meteorological conditions which prevailed during those 
years, which favoured the breeding of A. darlmgi even in localities where this 
species is usually not found. 

Let us now briefly examine which are these meteorological factors which 
favour the multiplication and dispersion of A. darhngi and thus give rise to 
malarial epidemic outbreaks. 

Diagram No. 1 shows the average rainfall at various points along the coast 
at Uitvlngt (1916-36), Ogle (1906-36), La Bonne Intention (1916-1936), Enmore 
(1913-1936), Bath (1900-37), Albion (1865-1936 A Port Mourant (1880-1936), and 
Skeldon (1906-36). 

These averages, from our particular point of view, bavo relatively little 
value, as the annual range of deviation is very considerable and irregular. In 
table I the annual rainfall at Bath Estate, from )900 to 1938, is shown as an 
example. One notes that the annual rainfall varied within the extromo limits 
of 51.83 inches in 1913 and 128.46 inches in 1938. 


Table I. 

Annual Rainfall at BtTii, West Coast, Berbice, 1900 — 1938. 


Ymr 

RmnfaJI 
ni nidus 

Ytur 

Rainfall 
in indus 

1900 

85.56 

1920 

53.12 

1901 

61.29 

1921 

74.34 

1902 

76.38 

1922 

84.45 

1903 

92.83 

1923 

72.04 

1904 

57.72 

1924 

74.32 

1905 

65.73 

1925 

52.03 

1906 

89.48 

1926 

54.17 

1907 

93.74 

1927 

104.74 

1908 

73.94 

1928 

76.86 

1909 

66.29 

1929 

79.08 

1910 

84.07 

1930 

83.52 

1911 

— 

1931 

69.84 

1912 

67.53 

1932 

98.29 

1913 

51.83 

1933 

115.30 

1914 

55.04 

1934 

67.99 

1915 

77.25 

1935 

95.02 

1916 

89.91 

1936 

104,35 

1917 

81.64 

1937 

87.28 

1948 

1919 

68.38 

1938 

128.46 

72.08 




Annual Average 77.17 inches 

Annual Maximum (1938) 128.46 inches 
Annual Minimum (1913) 51.83 inohea 



PtiATB I 


Platb II. 


RAINFALL 

IN 

INCHES. 



MALA HI A 
CASES. 


Months- I II III IV V VI VII vm IX X XI XII 

Ffglrc 2. — Iii the tidal river districts of the interior August and September are usually 
dry months ; the seasonal character of malaria is more distinct than on the coast, as the breed- 
ing of the carrier, A. darliw/i, is mainly dependent on the early summer rains. In 1926 a severe 
drought was experienced during the Miree months of the year, but heavy rains followed 
lasting from May to September with abnormally high atmospheric temperature. A . darlifyjt 
appeared in very large numheie and a severe malarial epidemic resulted which affected these 
districts for the following two years. Our graph illustrates the trend of the rainfall and 
malaria incidence cmves as registered at Mackenzie, on the Demerara River, in 1926. 




MALARIA Iff BRITISH GUIANA* 


7 


The total annual rainfall hag relatively little importance from a malario- 
logioal point of view ; we find, for instance, that malarial epidemics occurred 
both in 1926 and 193ft with rainfalls of 54.17 and 128.46 inches respectively ; 
conversely in 1933 with a rainfall of 115.30 inches no epidemic was observed. 
The seasonal distribution is ivhat matters . 

Heavy atmospheric precipitation during the late autumn and winter 
months, when the atmosphere is cooler and the trade winds strongest, is never 
associated with an increase in the number of Anopheles ; on the contrary, such 
rains appear to influence adversely these insects, and their number rapidly falls, 
the minimum incidence being observed in February and March. 

The incidence of malaria invariably declines during October, November 
and December, the healthiest months in this respect being February, March and 
April. The exceptionally heavy rainfall in December of 1933 and January, 
1934 which caused disastrous floods did not produce any appreciable lise in the 
incidence of Anopheles and consequently of Malaria. 

Failure of the autumn-winter rains is undoubtedly favourable to the 
survival of Large numbers of .1. darhngi ; a drought at this season is often the 
prelude to a malarial epidemic later in the year. 

The spring-summer rainy season which usually comes on in May and 
coincides with the period of highest atmospheric temperature and with the fall 
of the trade winds, always gives rise to active Anopheline breeding. If these 
rains are steady and continue throughout July and August, and possibly into 
September, especially if the temperature is unusually high, the breeding of 
A dnrhngt becomes both extensive and intensive, and the incidence of malaria 
rapidly rises. 

In localities which are usually free from malaria, and where under normal 
or average conditions, the physio-chemical properties of the surface waters are 
such as to render them unsuitable for the breeding of A . darlnu/t , the diluting 
action of heavy and persistent rains may so alter their characters as J;o transform 
them into attractive and productive breeding sites. During heavy rains, in 
July 1938, we found, for instance, A. Atlntarsis, usually an inland savannah 
species, abundant and breeding actively in rain water collections situated 
outside the sea wall at Bel Air. 

Observations carried out in the interior, on the Demerara River (1923- 
1932), indicate that the duration of the period intervening between the onset of 
the rains and the rise in the incidence of malaria varies in inverse proportion 
to the height of the atmospheric temperature. A high temperature speeds up 
both the development of the Anopheles from ovum to adult, and the evolution 
of the malaria parasite in the Anopheles, />., Anopheles breed more rapidly and 
become infectious in a shorter period after feeding on a suitable malarious 
subject 



8 


AORlOTOTtriUL JOURNAL OF BRITISH OTUHiU 


[X, L 

Increased nocturnal atmospheric humidity, which accompanies persistent 
rains, will favour the survival and flight of A . darlingi and thus increase its 
activity and dispersion, 

Tho ubiquitousness of favourable surface waters — resulting from heavy 
and persistent summer rains — in close proximity of houses and villages, will 
greatly reduce the hazards which the Anopheles must face in its long flights to 
and from its habitual breeding sites, as they will lav their eggs in the nearest 
suitable waters and return to the houses repeatedly to procure the blood meals 
they require ; a larger proportion of malaria infected Anopheles will, therefore, 
survive in close proximity of human habitations, and the transmission of malaria 
inevitably becomes extremely active. 

This is the mechanism by which the malarial epidemics of 192(1 and 1938 
originated both on the coast and in the tidal river districts of the interior. 

Diagram II illustrates relations between malarial (incidence and rainfall at 
Mackenzie in 1926. 

% 

Diagrams III and IV refer to the malarial epidemics at Skeldon and Bath 
in 1937 and 1938. 

The chronological sequence of the 1938 epidemic outbreaks in Berbice is 
of special interest : Skeldon, which is situated some 8 miles up the Corentyne 
estuary, was the first affected ; it suffered a mild epidemic in 1937 and again a 
severe outbreak commencing m June 1938. Albion was the next affected ; It 
suffered both in 1937 and 1938. This plantation is situated farther inland than 
the next, and the yards border on the cane cultivation and on sheltered bush- 
surrounded rice fields. Port Mon rant, which lies further north, in open 
country, suffered mild epidemics coming on late in August in both years. Bath 
was only very slightly affected in 1937 and was the hist to be involved in 1938. 
Ihe outbreak on this coastal estate was sharp and short ; A* darlingi which 
was extremely abundant in October had practically disappeared in January. 

Malaria, a alike other epidemic diseases, cannot spend itself in the oonrse of 
a few weeks or months ; once the infection is acquired, the disease evolves by 
relapses; even with the complete disappearance of the Anopheline carrier, the 
consequences of an epidemic continue to be felt for two or three years. Thus 
the localities of the Corentyne Coast which in 1937 had spleen rates of 2 or 3% 
now have rates of 32 and 24% ; in another locality of the west coast of Berbice, 
the rate has risen from 1 .5 in 1936 to 20.8% in 1938. 

^If we refer again to Table I, we observe a tendency in the annual rainfall, as 
registered at Bath, to increase during late years ; whereas from 1900 to 1926 
atmospheric precipitation reached 90 inches p.a., on only two occasions (1903 and 
1907) the maximum recorded being 93.74 inches, from 1927 to 1938, this has 
occurred no less than 6 times with 104 inches in 1927 and 1936 ; 115 is 1938 and 
128 in 1938. * 



MALARIA IK BRITISH GUIANA. 


9 


If this tendency persists malaria will undoubtedly become endemic in many 
localities which up to the present have enjoyed a remarkable freedom from this 
disease. This is particularly probable for the West bank of the Corentyne 
estuary, where the higher level of the land, the low soil salinity, the less active 
ventilation, the higher atmospheric humidity, the abundance of rice and cane 
lands coupled with the abundance of bush and tree vegetation, are all conditions 
of themselves favourable to the presence of A. darling i. 

PART V. WHAT MALARIA MEANS TO THE RURAL POPULATION 

OF THIS COLONY. 

The great majority of the rural inhabitants of British Guiana pass their 
whole existence exposed to the ravages of malaria ; they accept the disease as an 
inevitable neoessity. There exists no trace of popular instinct or tradition aiming 
to avoid the disease by intelligent location of settlements and villages as is 
usually found amongst indigenous populations of malarial countries. 

In the interior only the Aboriginal Indian builds his camp en high ground, 
on sand or gravel ; the immigrant from the coast, of negro, Chinese, Portuguese, 
east indian and mixed race, invariably settles and builds his house on the alluvial 
and intensely forested and malarial mud fiats which form the floor of the river 
valleys. 

Such a state of affairs is comprehensible when we consider that the mass of 
the present day population of the Colony descends from people brought to the 
country in the past to fill the requirements of the plantations (cotton, coffee, 
cocoa and sugar) which have always been the main raison d'etre of the Colony. 
These people were made to settle on the fertile alluvial plains, and trained to live 
where they were required. The habit so formed, in the presence of the very 
peculiar configuration and hydrological regime of the coastlands, has given rise 
to a rural population of somewhat amphibian customs ! 

Amongst the more educated classes, both in the country and towns, ordinary 
practical knowledge about malaria is remarkably deficient ; one notes a frequent 
tendency to camouflage the disease under other names suoh as “low fever,” 
“ biliousness,” etc. 

Public opinion in general appears definitely apathetic to Malaria which 
involves scores of thousands of people and causes> directly or indirectly, thousands 
of deaths every year, whilst it has shown considerable enthusiasm in relation to 
suoh relatively minor health problems as tuberculosis and leprosy which cause 
only an infinitesimal fraction of the mortality, disability and financial loss for 
which malaria is responsible every year. 

It may, therefore, be of advantage to conclude this series of articles»by the 
study of certain statistical data we have collected, which vividly demonstrate 
what malaria r eall y means to a large section of our rural population and to the 
Colony In general ; and what account must be taken of this particular problem 
ip sh e fra mi ng of any plan or scheme for land settlement and further agricultural 
development? 



10 


AGBIOT7LTTTRAL JOUSNAL OF BRITISH GUIANA. 


tx 1. 


Oar studies have been limited to the population of the sugar estates, which, 
in 1937 aggregated olose on 68,000 persons, i.e., 35% of the total coastal rural popu- 
lation of the counties of Demerara and Berbice. There is no reason to believe 
that conditions in the villages in the Bame areas are in any way better ; the 
oontrary is more probably the truth, as the villagers, whilst living in localities 
similarly and often less favourably placed, do not enjoy the advantages of estate 
residents in the form of free hospital and medical treatment. The sugar estates, 
in this connection during the last ten years have spent an average of close on 
$104,000 per annum on their hospitals only. 

In 1938 the sugar estates issued free of charge no less than 422 lbs. of 
quinine, i.e. 27% of the total amount of this drug imported into the Colony in 
1937. 

Dr. Boyd’s recent survey tends to confirm our surmise ; one of the highest 
spleen rates in the Colony was recorded from Lodge Village on the outskirts of 
Georgetown, and high rates were observed in villages on the East Bank. 

It is very difficult to obtain a correct idea of the damage done by malaria from 
an analysis of morbidity and mortality returns ; the ^reat majority of fever 
cases pass unreported and a great many more are incorrectly diagnosed. Malaria 
often causes death in its acute form ; most of such deaths are undoubtedly 
registered under the correct diagnosis, but the highest mortality is caused by 
chronic malaria which entails extensive and varied organic degenerative pro- 
cesses ; the clinical picture is complicated and a great many such deaths are 
registered under diagnoses obher than malaria, as for instance, cachexia, maras- 
mus, dropsy, nephritis, debility, senility, etc. 

On the sugar estates, an average of 125 out of every 1,000 deaths registered 
are directly ascribed to malaria ; that, in itself, constitutes an alarmingly high 
rate. 

The trend of the vital index ( 1 'curve, i.e. the ratio of births to every 100 deaths 
registered per annum, studied in relation to the incidence of malaria, as indicated 
by the spleen rate, furnishes, we believe, the most reliable index as to the effect 
of endemic malaria on a community. 

We have carried out such an investigation on all the sugar estates of the 
Colony from the year 1920 to 1937, classifying them in 3 groups (A, B and C) 
according to their spleen rate as determined in 1937, i.e. before last year’s 
epidemics. 

Diagram No. V refers to 5 estates (group A) aggregating a population of 
20,967 (Plantations Diamond, Bath, Albion, Port Mourant and Sheldon) all of 
which, under average conditions, are practically free from endemic malaria. In 
1937 all these estates had spleen rates ranging from 0.1 to 5%. 


<lj The term “ Vital Index ’’ has been suggested by Pearl “ to designate that measure of a 
population’s condition whioh is given by the ratio of births to deaths within a given time.” 
Of this%idex this Author states : ‘‘It may fairly be said that there is no other statistical 
constant which furnishes so adequate a picture as this of the net biological status of a popula- 
tion as a whole at any given moment.” And again : “ After much stnay of it 1 am coni meed 
that no single figure gi\ es so sensitive a measure of the vitality of a nation or any sub group 
of people as this does.” R. Pearl Introduction to Medical Biometry und Statistics.— 1923, 



Plate V. 



Diagram V. — In this and the tvo following diagrams, which should l»e carefully com- 
pared, tlio Vital Index or births to deaths ratio, is studied from 1920 to 1937 over the* whole 
sugar estate population, classified into three groups according to the incidence of malaria ns 
indicated by the spleen rate. 

Y* 1 ® 100-100 base line indicates 100 deaths ; the graph shows the number of births for every 
100 deaths registered per annum. When births exceed deaths, the graph runs above the 
base line ; when births are fewer than deaths, then the graph falls below the base line, (see 
diagrams VI and VII). 

The above graph shows the trend of the crude Vital Index on a group of five sugar estates 
aggregating a population of 20,907, which are free from endemic malaria. As a yearly average 
from J920 to 19B7 there were 244 births to every 100 deaths, births being constantly and 
considerably m excess of deaths. 

The average annual infant mortality (I.M.) waB 113 per 1,000 live births. 



PLATE VI 


1920 ltrjl lt>22 3923 1924 192' 1926 1027 1928 3929 1930 1931 1932 1933 1934 1935 1936 1937 

Diagram VI. — Crude Vital* Index curve, 1920-1937, from a group of 10 Sugar Estates, 
aggregating a population of 29,832, which are subject to endemic malaria, (spleen rate from 
5 to 30%). As an average for the whole period there were 152 births to every hundred deaths. 
In two years there were more deaths than births. The average annual Infant Mortality 
(LM.) was 155.9. 




MALARIA IN BRITISH GUIANA. 


11 


Throughout the 18 year period covered, the number of births on these 
estates was constantly and very considerably in excess of the number of deaths ; 
as an average there were 244 births to every 100 deaths. The curve has a very 
marked upward trend. In the early part of 1920 a severe epidemic of malaria 
swept the Colony (see Diagram II) ; it appears likely that this epidemic was 
connected with the fall in the vital inder which occurred in 1927 and 1928. In 
that case we may expect to witness again a similar fall during 1939 and 1940 
as a result of last year’s epidemics. 

Diagram No. VI illustrates the vital index curve from 1920 to 1937 for 10 
estates (Group B) aggregating a population of 29,832 (Plantations Uitvlugt, 
Leonora, Versailles, Providence, Farm, Vryheid’s Lust, Non Pareil and Enmore) 
which are subject to endemic malaria, with spleen rates not exceeding 30%. We 
observe that the general level of the curve has fallen very considerably (compare 
with Diagram V). In two years, 1922 and 1923, there were actually more deaths 
than births and in 1928 the two just balanced. As an average, for the whole 18 
year period, there were 152 births to every 100 deaths, i.r. a fall of 92 births from 
the average shown by the non-malarial estates included in Group A. 

Diagram No. VII gives the vital index curve from 1920 to 1937 for 7 sugar 
estates (Group 0) aggregating a population of 15,870 (DeKinderen, Wales, Ogle, 
La Bonne Intention, Lusignan, Blairmont and Providence, Berbice) on all of 
which malaria is highly endemic the spleen rate being constantly above 30%. 
The curve shows a fall to yet a lower level when compared to the two preceding 
diagrams and in the years out of 18 (1921, 22, 23, 28 and 1933) there were more 
deaths than births. For the whole period, as an average, there were only 119 
births to every 100 deaths, t.e. a decline of 125 births on the average of the non- 
malarial estates included in Group A. 

In Table II we present certain other vital statistical data, referring to the 
1932-37 period and to the sugar estate population of the whole Colony classified 
according to the spleen rate, as above, into 3 groups, A, B, and C. 

Table II. 

Malaria Rate in relation to birth rate, maternal mortality, infant 
mortality, and stillbirth rate, annual averages 1932 — 1937. 


Estate Group 

A 

B 

C 

Population 

20,907 

29,832 

15,870 

Spleen Rato 

Under 5% 

5% to 30% 

Over 30% 

Average Annual Birth Rate 

32.1 

25.0 

20.7 

Maternal Death Rate 

10.6 

21.4 

21.2 

Infant Mortality 

113.0 

155 9 

170.9 

Stillbirth Rate 

47 

78 

* 92 

These figures indicate 

that the population 

of the malarial 

areas is less 


fertile as showij by the decline of the birth rate in parallel with the increase of 
the spleen rate. 



12 AGRICULTURAL JOURNAL OF BRITISH GUI AHA, [X, 1. 

The hazards of child bearing are similarly increased as shown by the twofold 
rise in the maternal mortality and the stillbirth rate in gronps B and C. 

The chances of survival of the infants decrease as the malarial rate rises ; the 
same could be said for young children between 1 and 4 years of age. 

These diagrams aud statistics indicate most clearly how deeply malaria 
affects a population ; its ravages are not limited to the morbidity and mortality it 
determines; the very vitality of the community is involved and its normal 
tendency to reproduce and expand inhibited. Such a loss of vitality inevitably 
reflects itself on the productiveness, *>. on the economic value of both the indivi- 
dual and the community. 

In British Ouiana, with its peculiar geographical, climatological and excep- 
tional hydrological conditions the malarial problem, as we have shown, presents 
itself as one of unusual magnitude and with characters which are probably 
unique ; it is intimately connected with the two basic agricultural industries of 
the Colony. 

In spite of such difficulties we feel confident, bn the base of our findings, 
which have revealed certain limitations in the biology of A. dnrlingi which may 
be exploited to its detriment, that malaria can be successfully controlled if not 
eradicated in a considerable portion of the inhabited coastland of this Colony. 



Plate VII* 



Diagram VII.— Crude Vital Index curve, 1920-1930, from a group of 7 Sugar Estates, 
aggregating a population of 15,876, which are subject to severe endemic malaria (spleen rate 
30 to 60%). As an average over the whole period there were 119 Liuba to every hundred 
deaths In five years there were more deaths than births* The average annual Infant 
Mortality (I,M.) was 170.9 per 1,000 live births. 










RESULTS OF PADI VARIETY TRIALS, 1938 

RY 

P. A. Chan-Ciioono, b.sc., a.i.c.t.a. 

Assistant Plant Breeder, Department <>J Agriculture. 

Introduction. 

In the Agricultural Journal of British Guiana, Vol. IX, pp. 98— 9i>, an 
account was given of the variety trials which were laid down for the 1938 
Autumn Crop. Fifteen of the older varieties which had been tested in previous 
years were retained, some to be used as controls, others to be given a final test. 
Thirty -four varieties which had passed through the progeny rows at the 
Georgetown and Henrietta Experiment Stations, for purification and preliminary 
yield testing, were considered promising enough for trials ; seven of these were 
hybrids bred at the Georgetown Station. Three varieties found in mixed 
cultivations in the Corentyne District, were also included. 

The sites of these variety trials were as follows : 

Berbiee: Whim Under the supervision of Mr. J. D. 

and Gillespie, Agricultural Superintendent, 

No. 70 and later, of Mr. E. M. Morgan, Asst. 

Agricultural Superintendent. 

W/0, Berbiee Under the supervision of Mr. E. M. 

Morgan, Asst. Agricultural Superinten- 
dent. 

Demerara: Georgetown Rice Under the supervision of Mr. E. M. 

Station. Peterkiu, Agricultural Superintendent. 

Vreed-en-Hoop Under the supervision of Mr. E. G. 

Benson, Agricultural Superintendent. 

Ejsequibo : Henrietta Under the supervision of Mr. A. A. 

Abraham, Agricultural Superintendent. 

Two classes of trials were laid down — Class -^A (Standard) and Class B 
(Individual District). The purpose of the Standard trials was to test the more 
promising varieties in all the districts, while the Individual District trials 
contained certain additional selected varieties whioh it was considered desirable 
to test in different districts. 

Crass A (Standard) Trials. 

Six Class A trials, two of long-grained varieties and four of medium-grained 
varieties, were laid down at each of the stations Georgetown, Henrietta and 
Whim. Long-grained controls (Demerara Creole and D 221) and medium-grained 
controls (D 99 and D 114) were included in each group. Unfortunately at Whim, 
the water supply failed at flowering time, so that five of the trials had to be 
discarded on account of the very poor or no yields obtained. 

The trials consisted each of five randomised blocks, containing nine, ten 
or eleven varieties in each block. 

The results are presented in Tables I and XI. 



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1 RESULTS OE PADT VARIETY TRIALS, 1938 


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16 AG&ICffLTtTBAL JOtTMUt Of BRITISH GtJtAHA* £X 1. 

In the six trials at Georgetown, shown in Table I, the following revolts 
were obtained : 

Trial 1 : The four leading varieties are D 114, D 99, D 259 and Jaisingh. 

The remaining six varieties are significantly inferior, except 
Kalyaman which is inferior to D 114 only. 

Trial 2 : This trial yielded no significant result. 

Trial 3 : D 99 was easily the leading variety, while D 108 was definitely 
the worst. Unity and D 162 were very nearly significantly 
inferior to D 99, but were not superior to the rest. 

Trial 4 : Apart from D 262 and D 261, which were definitely the worst 
varieties, there was very little to choose between the varieties in 
this trial. 

Trial 5 : I) 257, D 256, D 99 and D 111 were definitely better than the last 
five varieties in the list. Demerara Creole and D 246 were 
significantly inferior to the remaining nine varieties. 

f 

Trial 6 : This trial yielded no significant result. 

From the variety trials at Henrietta, shown in Table II, the following 
conclusions may be drawn : 

Trial 1: The leading varieties were D 99, D 111 and Jaisingh, these being 
significantly superior to the rest, except D 259 which was 
exceeded only by D 99. 

Trial 2 : D 99 was sig lificantly superior to D 114, which in turn was 
significantly superior to the rest. Kalyaman, Nickerie Patna and 
D221 followed with significant superiority over the others. 

Trial 3 : D 99 again proved the best variety. D 94 and D 1 14 came next, 
but D 94 alone was significantly superior to D 109 and D 162. 

Trial 4 : D 99 and 114 led in this trial, both being significantly superior 
to the others. No. 79 and D 258 showed no difference between 
themselves, but both were significantly superior to the rest. 

Trial 5 : D 99 once more came ahead of the other varieties. The remainder 
were bracketed together, with the exception of Demerara Creole 
and D 221 which were significantly the worst. 

Trial 6 : D 99 led again, with D 114 and 19 — 37 coming second, both 
proving significantly superior to the rest. 

The one Class A variety trial from Whim (a trial with medium-grained 
varieties) gave the following results : 



MRUWa OP P\Dl VARIETY TRIALS 1938, 


17 


Table III. 


Variety 

Yield per acre 
lb. 

D 255 

4,244 

D 256 

3,812 

D 221 

3,708 

Demerara Creole 

3,568 

I) 247 

3,512 

D 114 

3,108 

D 246 

3,048 

D 116 

2,816 

D 250 

2,416 

11 99 

2,238 

Sig. Dill. P — .05 

523 

D 255 and D 256 were the leading varieties, 

1) 221, Demerara Creole and 

D 247 followed, bat only D 221 was significantly 
varieties. 

superior to the remaining 

Clvss B (Individual District) Trials. 

These trials were laid down at Henrietta (Esseqaibo), Vreed-en-Hoop 

(West Demerara) and No. 70 and W/C, Berbice (Berbice). The trial at Henrietta 
contained selected long-grained varieties, tested against D 114 as control ; the 
trial at No. 70 contained old varieties and three varieties local to that district. 


The results are shown in Table IV. 



Table IV. 


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BBSUI/TS OF PADI VABIBTY TBIALS, 1938. 


19 


From these, the following conclusions may be drawn • 

Trial 1 : At Henrietta, the first five varieties, 1 — 1, D 114, 18 — 4, Seymour 
S, and 25 — 5, showed no significant difference between themselveB, 
but of these, 1—1 alone was significantly superior to the six last 
varieties in the list. Sue was definitely the worst variety. 

Trial 2 : At No. 70, there was no significant difference between the first five 
varieties, D 97 B, No. 79, D 114, Benab No. 79 and Kalyaman, but 
D 97B was significantly superior to the last five varieties listed. 

Trial 3 : The trial at W/C, Berbice yielded no significant results. 

Trial 4 : At Vreed-en-Hoop there was equality among the first four 
varieties i) 1 14, Jaisingb, D 99 and I) 110 : of these D 114 alone 
was significantly superior to the five varieties at the end of the 
list. 

Conclusions, 

A consideration of the present results and those obtained in previous years 
leads to the following general conclusions : 

1. Judged from the yield standpoint only, D114 is the best of all the 
varieties available. If certain milling difficulties can be overcome this 
variety will prove very valaable to grower and producer alike. It has 
been compared with Demerara Creole, No. 79 and Blue Stick on many 
occasions with the following results : 

In 42 trials it ontyielded Demerara Creole by 404.3b lb. per acre. 
,, ,, ,, ,» No. i 9 ,, 31s. sO ,, ,, ,, 

,, Is ,, ,, ,, Blue Stick ,, Jbh.lw ,, ,, i, 

2. No well-tested long-grained variety as yet offers as a substitute for 
Demerara Creole. 

3. D 99, D 109 and D 110 are heavier yielders than the standard 
medium-grained varieties No: 79 and Blue Stick, and are worthy of 
commercial consideration. In the meantime they are being examined 
as to drought resistance, a characteristic of No. 79. D 99 has a longer 
vegetative period than No. 79. 

4. The following varieties should be tested further : 


Long-grained . 


Mcdi u m-gra i n ed. 


D 11(5 D 94 

I) 253 D 1152 

D 254 1) 246 

D 259 D 247 

29-37 D 250 

Jaisiugh D 255 

Nickerie Patna D 256 

1) 257 
Unity 



20 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[X, 1. 


5. The following varieties may be dropped from farther trials : — 


D 91 

D 251 

15-37 

Padi Berbice 

D 108 

D 258 

17-37 

Seymour 

D Ho 

D 2G1 

18-37 

Kalyaman 

D 193 

D 262 

19-37 


D 221 

13-37 

23-37 



Acknowledgment. 

Thanks are due to the Director of Agriculture, the Deputy Director of 
Agriculture (Acting)and the Sugar Agronomist and Plant Breeder lor their views 
and suggestions as to the presentation of these results. 



RESULTS OF RECENT EXPERIMENTS WITH SUGAR CANE 

BY 

C. HOLMAN B. WILLIAMS, M.A., a.i.C.t.a., Dip. Agr., 

Sugar Agronomist and Plant Breeder, 

Department of Agriculture . 

The results of a large number of variety and manurial trials with cane, 
harvested during the last six months of 1938, have been printed in an 
abbreviated form and distributed locally to sugar estates and managers and others 
intimately connected with the industry. The data will appear and be fully discussed 
in Sugar Bulletin No. 8 , which is due to be issued about July, and will deal 
with the experiments harvested during the year ending June 30. In the 
meantime, however, attention may be drawn to some of the points which have 
emerged. 

Of the canes which have been harvested as plants, first and second ratoons, 
Co. 213 has been well tested and considerable reliance can be placed on its 
position with regard to the standard canes. Some estates are making commer- 
cial tests of this cane* which appears to be an economic sugar produoer, and 
others are advised to do likewise. D. 49/30 and D. 66/30 have also been fairly 
well tested. Though neither is likely to outfield P.O.J. 2878, the former 
may be expected to out yield Diamond 10. More experimental data are being 
sought from P.O.J. 2753, D. 50/30, D. 75/30, D. 67/30 and D. 150/30 which ail 
continue to show promise. In the meantime nurseries of these canes should be 
established and extended. 

D. 419/33 (Co. 281 x Diamond 10) heads the list of canes reaped only as 
plants and first ratoons. It has been harvested twice as a plant and once as a 
first ratoon and promises to be satisfactory both as regards cane yield and juice 
quality. 

Of the seedlings harvested in plant cane trials only, D. 552/33 (D. 219/30 
x Diamond 10) and D. 166/34 (P.O.J. 2878 x Sorghum) are worthy of note. The 
former, in a single test, gave eight tons of cane per acre more than P.O.J. 2878 
and a juice just slightly inferior to that of the standard. D. 166/34, a variety 
which has been outstanding in the nurseries at Sophia, has given the following 
average plant cane results in two experiments (La Bonne Intention and 
Leonora) where it was compared with Diamond 10 : 


Variety, 

Cano, 

Tons/acre. 

Sucrose, 

% Cane. 

Glucose 

Ratio. 

| 

Juice 

Purity. 

Sucrose, 

Tons/acre. 

D. 160/34 

48.07 

14.02 

7.22 

88.0* 

7.11 

Diamond 10 

39.94 

14.00 

0.53 

90.1 

5.82 



22 


AGRICULTURAL JOURNAL OF BRITISH GUIANA, 


[X, 1, 


The fertiliser results may be summarised as follows 

1. Further confirmation is reported as to the sulphate of ammonia require- 
ments of frontland, /.<?.* 2 cwt. per acre for plant canes and 4 cwt. each * 
for first, second and third ratoons. Increased evidence is available in 
support of much heavier dressings of nitrogen (probably of the order of 
120-140 lb. per acre for both plants and ratoons) for pegassy clays and 
such applications are likely to yield a profit. If, however, they are given 
in the form of sulphate of ammonia (5-6 cwt. per acre), a dressing of 
one ton of limestone at every replanting seems essential if the useful 
life of these already very acid soils is not to be endangered. 

2. Nicifos (18 : 18) was tested on first ratoons at five pegassy clay sites 
and on plant canes at four frontland sites. It increased first ratoon 
yields in Field 36 S.D., Cane Grove, where it had had an excellent 
effect in the plant canes, and the total difference in its favour for two 
crops is impressive. The area is deficient in phosphate and the result 
is probably due to none ol the other fertilisers being accompanied 
by phosphate. Thus in Field 10 0., Wales, where both trial sites 
were somewhat deficient in phosphate, it did not differ significantly 
from nitrbchalk plus basic slag in effect on the plant canes or 
first ratoons. Similarly in Fields 64 and 70 Z., Uitvlugt, it was 
not better than nitrochalk plus basic slag for plant canes and on first 
ratoons it proved inferior in Field <54 Z and of equal merit in Field 
69 Z., Uitvlugt. Nicifos was compared with sulphate of ammonia and 
nitrochalk four times with plant canes on frontland. It did not produce 
a significantly different yield in any instance but at Leonora the canes 
from the nicifos plots were sweeter than those from the sulphate of 
ammonia plots but not than those of the nitrochalk treatments. 

3. Nitrochalk was tested with first ratoons five times on pegassy clay and 
with plants four times on frontland. On the pegassy clay the yields did 
not differ statistically from those given by nitrogen-equivalent dressings 
of sulphate of ammonia, thus confirming the plant cane results where in 
only one out of five instances was there any difference. Further, in com- 
bination with basic slag, it proved as efficient or more so than nicifos for 
both plants and ratoons. On frontland there was no significant difference 
between the effect of nitrogen-equivalent dressings of nitrochalk and 
sulphate of ammonia on plant cane yields. At Leonora, however, nitro- 
chalk gave a definitely sweeter cane than sulphate of ammonia. 

It has been proved that the cane soils of the Colony are rapidly 
becoming more acid and that the process is accelerated by the increased 
Hie of sulphate of ammonia. On the other hand, it is clear that heavy 
nitrogen applications are economically sound and the compromise has 
been suggested, and largely adopted, of supplying the nitrogen in the 



RBftULTa OB' RECENT EXPERIMENTS WITH SUGAR CANE. 


23 


form of sulphate of ammonia and applying a dressing of one ton of lime- 
stone per acre at each replanting to counterbalance the acidifying effects 
of the sulphate of ammonia. 

A possible alternative procedure would be to employ a nonacidify- 
ing nitrogenous manure, and it now appears that nitrochalk is deserving 
of careful consideration and commercial tests by the sugar estates. This 
manure contains a lower percentage of nitrogen than does sulphate of 
ammonia and more would have to be used to obtain a nitrogen-equivalent 
dose, the proportion being roughly four of nitrochalk to three of sulphate 
of ammonia. Since the two fertilisers are quoted at approximately the 
same price per ton in England, it follows that the ratio of cost would 
also be in like proportions. On the other hand yields are the same from 
nitrogen-equivalent doses of the two fertilisers and at iirst one may be 
tempted to forego what appears to l>e a considerable increase in cost (3 : 4) 
for no immediate gain. If, however, consideration is given to the fact 
that with the sulphate of ammonia one should buy and apply a ton of 
limestone at every replanting whereas the nitrochalk will not acidify the 
soil but, on the contrary, supply it with a considerable amount of calcium 
carbonate, tho true increase in cost from the use of nitrocualk will be 
seen to be negligible. 

It is suggested that each estate take snyrdf fields through a complete 
cycle using only nitrochalk as a nitrogenous manure, and that where the 
estate possesses both soil types several fields in each area should be so 
treated. 

1. Nitrate of soda appeared in five first ratoon trials on pegassy clay. In 
the plant canes it had not given statistically different yields from 
iiitrogen-equivalent doses of sulphate of ammonia or nitrochalk. In the 
first ratoons it proved equivalent to sulphate of ammonia in all five trials 
but was definitely inferior to nitrochalk in one out of the five (Field 36 
S.l)., Cane Grove). Oil the whole -it seems a Jpss likely substitute for 
sulphate of ammonia than does nitrochalk. 

5. Superphosphate of lime had no effect on the yield of first ratoons (Field 
2011.) at Port Mourant but had a definitely adverse effect on juice purity. 
It will be remembered in this connection that a medium dose of this 
fertiliser had an adverse effect on tho sucrose content of the plant canes 
in Field 23 R., Port Mourant. The plots in this field were tested as first 
ratoons for any residual effoct of the plant cane pliospbatic dressings but 
there was none. Phosphatic applications cannot be advised for this 
portion of the estate. On second ratoons, superphosphate of lime had no 
effect in Field 81 R.H., Rose Hall, but a medium dose definitely increased 
cane yield in Field 26 lip., Blairmont. As in the case of sulphate of 
potash there was no effect on yield in the two earlier crops and the 
present jesult appears to be the cumulative effect of three dressings. 



u 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


tx, 1. 


6. Sulphate of potash had no significant effect on second ratoons on 
frontland at Rose Hall (Field 81 R.H.,) but gave a definite increase in 
second ratoon yield on Field 26 Rp., Blairmont. In the latter field there 
had been no effect on plant cane or first ratoon yields. It seems that the 
present result is the cumulative effect of three applications and that 
potash-fixation by the soil may be involved. On first ratoons at Port 
Mourant there was no residual effect from plant cane applications (Field 
23 R.) or from applications to first ratoons only (Field 20 R.) 

7. Manganese ore, from a local deposit, was tested on a pegassy clay. It 
had no definite effect on the plant cane yield but adversely affected the 
juice purity. 



CATALOGUE OF THE LEPIDOPTERA RHOPALOCERA 
(BUTTERFLIES) OF BRITISH GUIANA 

BY 

ARTHUR HALL, F.R.Ent.s. 


Introduction. 

British Guiana is, with the exception of India, the richest of all the British 
Dominions in Lepidoptera, but it is remarkable how little has been written 
about them. When attempting to obtain information on the subject previous to 
my first visit to the country in 1929 I was only able to discover isolated records 
of the butterflies scattered through all sorts of books and periodicals 
of various dates covering more than a century. Many of the species 
described by the older authors with such vague localities as “ Guiana ” 
and “ South America*’ may have come from our Colony, and the very large 
number recorded and figured in the classic work of Cramer as long ago as 
1 779-1791 from the neighbouring Dutch settlement of Surinam gives some idea 
of what we may expect to find in British Guiana. But the very few competent 
entomologists who have visited the latter country have contented themselves 
with collecting specimens without leaving any account of their expeditions and 
in view of the rapidly increasing number of scientific travellers who now 
come to British Guiana and the great importance recognised as attaching to 
geographical distribution and variation it has been thought that a preliminary 
Catalogue of the Rhopalocora known to inhabit the Colony is desirable. As one 
would expect from the nature and situation of the country the butterfly fauna 
of British Guiana is mainly that of the great Amazonian Region with a slight 
but distinct admixture of Venezuelan elements. It has, however, a number oi 
interesting peculiarities of its own. A feature which it shares with the lower 
Amazon is the great abundance of sprrtrs as compared with the comparatively 
small number of individuals. Migratory swarms of such species as Colon#'! ta 
statiro and the moth Urania leilas are not infrequent, especially "along the 
rivers but with these exceptions one rarely meets with those large masses of 
butterflies so often to be seen in hilly districts even in temperate regions and it 
is sometimes possible to walk a mile or more in the Guiana forest without seeing 
any butterflies at all except perhaps a few small Satyridae . On the other hand 
in favourable localities the collector can easily obtain over a hundred species 
within two or three days and hardly a day passes without yielding something 
which he has not met with before. Although the fallowing catalogue includes 
well over seven hundred species the fact that many species, particularly of the 
smaller kinds, which are known from Dutch Guiana have not yet been recorded 
from our side of the frontier renders it certain that many more remain to be 
discovered an<^ inasmuch as the whole southern half of British Guiana from 



26 • AGftteULfnftAL JOTjENAL OP MMHlf QUIAJRA. It, 1. 

Tamafcumari to the Brazilian frontier is practically unexplored by the lepidop- 
terist, it would not be surprising if the number of butterflies occurring within the 
Colony should ultimately be found to exceed one thousand species. In a 
country having a land frontier on three of its four sides and without marked 
physical differences from the adjacent territories no great number of peculiar 
forms can be expected, but there is nevertheless a small number of species and 
sub-species which have not hitherto been recorded from anywhere else. One of 
the most historically interesting of these probably peculiar species is Heliconian 
hecale . This was figured by Cramer in 1774 under the name of Papilio pasifhoe 
from “ Surinam ”, but no collector for more than a century has met with it 
anywhere east of the Demerara River and as the Dutch Colony at the time 
when Cramer’s work was published included the present counties of Berbice and 
Demerara it not only seems probable that his specimens came from what we 
now know to be its area of distribution, that is, the area between the Demerara 
and Essequibo Rivers, but it gives rise to the interesting speculation as to 
whether many of Cramer’s other Surinam species may not have come from 
what is now British Guiana. 

Amongst the different families of butterflies the Danmdae, amongst which 
are now included the transparent and mimetic Tlhon^unae are in rather small 
numbers (35 species), as is also the case oil the lower Amazon. The Nnhjndw 
with 45 species^ are fairly well represented and the Brasnolalae although often 
unnoticed on account of their crepuscular habits, have 15 species, a rather larger 
number than in most of the adjacent countries. The seven species of Morpho is 
a large number for such a small area, and these of course never escape the notice 
of all those who visit the forests. 

In the great family of Nj/nijdialtdar the Hilnonunae are the most olten 
noticed owing to their bright colours and abundance in individuals but the 
Acraetnae which are often so abundant in the Andean regions may almost be 
said to be conspicuous by their absence, the only two species both being rare. 
The true KynwhuUnne with 08 species are less abundant both in species and 
individuals than is the case in the mountainous parts of the continent. The 
Enjcimdae with nearly 190 species are as strongly represented as anywhere else 
in the world, tniy family having its headquarters in Guiana and the lower 
Amazon, but they are far from being such a prominent element in the fauna that 
a mere catalogue would seem to suggest, many species being both rare and 
inconspicuous. 

The Papdiomdao have 27 species, the same number as is known from the 
whole of the lower Amazon, but the Piendae with 29 species are more poorly 
represented than in almost any other South American district of equal extent 
although the number of ” whites ” and 44 yellows ” nearly always to be seen 
along the banks of the rivers would give a contrary impression. The smaller 
Lycaemdao and Henpendae have not yet been sufficiently collected to give any 
just ifea of their numbers and it is in these two families and in the hnjcinidae 
that the greatest number of additions to our list is to be expected. f 



PLATE VIII. 



pi K . | . — Xapeomtifs htp/ia Lodm. Female. * 

Fig. 2 ,— C* rat* mn mnttUa cnnncra Mibsp. no\. remale (l,\pe). 
Figl 3. -Psntthwtidn tr ana Hall. Male ( T\ pe). 

Fig. 4 ,—ffcficonttis hrcit le clear* i Hall. Male. 

F|g. 5. — Cataqramnui ttlas Mull. ^Female l nderside. 

Fig. 6. -Pt/rrhoijttra xtratonicu* Frulist. Female. 

Fig. 7.— Anna pitht/nxa mount i Hall. Female. 

Fig. 8 . — Antirrlura tat/t/clina rotftcat/t Mibsp. mu bemale 
Fig. g .—Dixmorphia crista roraimtv subsp. no\ (T>pe). 

(All figures slightly reduced). 




CATALOGUE OF tHt LBPIOOPTBBA RHOPALOCiRA OF BRITISH GUIANA. 2? 


The records in the present Catalogue are taken chiefly from the following 
collections, all of which have been carefully examined : 

(i) The British Museum (Natural History). This includes the large 
collections made by H. Whitely on the Mazaruni, at Annai on the Essequibo, at 
Takutu, Quonga, and on the Carimang or Karana ng River (the former is the 
Spelling on the labels and is therefore here adopted), and at other places on his 
journey to Mount Roraima ; by W. Schaus at Omai and on the Essequibo ; by G. 
Rodway and others on the Demerara River ; by H. Patoir on the Berbico and 
many other specimens received from various collectors. With regard to these 
British Museum localities it may be well to note that the species labelled “ Mt. 
Roraima ” are practically all lowland forms and were evidently not collected at 
any great elevation. We have not been able to locate Quonga which was 
presumably some now abandoned settlement near the Upper Mazaruni or its 
tributary the Carimang River. 

(ii) The Georgetown Museum. This contains a fairly representative 
collection of the butterflies of the country ; unfortunately the specimens have no 
exact locality labels but the majority are said to have come from the Demerara 
River. 

(iii) Collections made by W. J. Kaye and his collector H. Roberts, chiefly 
at Tumatumari and on the old Potaro Road. 

(iv) Specimens collected by myself at Parika at the moulli of the Esse- 
quibo and at Bartica and Mabaruma (N. W. District) in December 1 920 and 
January 1930 and again at Parika, Bartica and the Kaieteur Falls in February 
and March 1930. 

(v) The collection of the Entomological Division of the Department of 
Agriculture, British Guiana. 

A small but very interesting collection made by G. A. Hudson on the Upper 
Kutari River and Upper Corentyne near the Brazil-Kurinam frontier has quite 
recently come to the British Museum and still later a few specimens obtained 
by Major Beddington near the Oronoque-New River confluence in the same 
region, but with these exceptions records from the eastern part of the Colony, 
the Rupununi Savannahs and the mountains of the S. W. frontier are very scant 
and more information about the species found there would be very welcome. 

Lastly, I have come across a paper by Dr. Roger Verity of Florence in the 
Mem. Soc. Ent, Italiana for 1934 on the butterflies collected by the Beccari 
Expedition and several species only recorded from this source are here included 
in the addenda. 

I have particularly to thank Messrs. N. D. Riley of the British Museum 
(Natural History), L. D. Cleare of the Department of Agriculture, Georgetown, 
and W. J. Kaye, F.R.E.S., for their assistance in compiling the present Cata- 
logue. A special debt of gratitude is also due to Professor J. S. Dash, Director 
of Agriculture, for kindly consenting to publish it in The Af/nculhnril Journal. 



AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


28 


£x, i. 


Family DANAIDAE. 

Sub-family DANAINAE. 

1. Danais archippus. 

Papilio archippus , Fab., Ent. Syst., Ill, (i), p.49 (1793). 

Generally common. Larva conspicuous on Asclepias. 

2. Danais eresimus. 

Papilio eresimus , Cramer, Pap. Exot. II, t. 175, G.H. (1779). 
Annai. Apparently scarce and local. 

3. LYCOREA PAS1NUNTIA. 

Papilio pasinantia , Cram., Pap. Exot. IV, t. 310, A. — C. (1782). 
Omai ; Annai ; Mabaruma ; Potaro Road. Sometimes common. 

4. LYCOREA CERES. 

Papilio ceres , Cram., Pap. Exot. I, t. 90 A. (1779). 

Annai ; Quonga ; Mabaruma ; Potaro Road. Locally common and very 
variable. The tendency for the marginal and median bands of the hind wings 
to unite so as to form a broad black outer patch is characteristic of the Guiana 
forms of the mimetic group of which this species is probably the primary model, 
the other members of the association being Ilirsufis harmonia , Melinaea 
mneme, M. crameri , Meehan it i s polt/mnia , J/. pannifera , the three species of 
Ceratinia and Heliconius numata . 

Sub-family— ITHOMIINAE. 

5. Thyridia confusa. 

Methona confusa , Butler, Cist. Ent. I, p. 151 (1873). 

Annai ; Potaro River ; Kuturi River (G. A. Hudson), 

6. HlRStJTIS HARMONIA. 

Papilio harmonia , Cramer, Pap. Exot. II, t. 190, D (1779). 

Annai ; Kuturi River. Always scarce and local. 

7. Melinaea mneme. 

Papilio mneme , Linnaeus, Syst. Nat. I, (2), p. 756 (1767). 

Generally common in forests. 

8. Melinaea mediatrix. 

M, mediatrix, Weymer, Stett. Ent. Zeit. LI, p. 282. 

Common with the foregoing and sometimes even more abundant. A 
frequent aberration is mauensis Weym. in which the hind wings have two 
separate bands. 

9. Melinaea mnasias tecta. 

ilf. mnasias tecta , Haensch in Seitz, Gross-Schmetterlinge V, p. 124 
* (1909). 

Described from British Guiana. Mr. W. J. Kaye has a specimen from the 
Potaro Road. 



CATALOGUE OF THE tKPJDOPTERA RHOPALOCERA OF BRITISH GUIANA. 20 


10. Melinaea KGINA. 

Papilio pghniy Cramer, Pap. Exot. II, t. 191 D (1779). 

Annai ; Omai ; Carimang River ; Potaro River ; Uppor Corentyne. 

11. Mechanitis polymnia. 

Papilio polymnia , Linn., Mus. Ulr. p. 224 (1704). 

Abundant in most wooded places. 

12. Mechanitis pannifera. 

M . pannifora , Butler, Cist. Ent. II, p. 150 

Rather more local than M. polymnia but often abundant. Annai ; Omai ; 
Takutu ; Mabaruma ; Kaieteur Falls. 

13. Aprotopos psidii. 

Papilio pnidii Linn., Mus. Ulr. p. 228 (17G4) 

Potaro River (W. J. Kaye); Kuturi River (G. A. Hudson). 

14. Callithomia aijexirrhoe. 

(7. alcxirrhor , Bates, Trans. Linn. Hoc. XXIII, p. 522 (1862). 

A series labelled “ British Guiana, Parish” in the British Museum. 

15. Ceratinia mutilla 

Tihomnt maliUa y Hewitson, Ex. Butt. IV, Ithomia t. 25 f. 153 (1867). 
Domerara River ; Carimang River ; Bartica ; Mabaruma. In the British 
Museum there are three pairs from Mt. Roraima which represent a local race 
having the two black bands of the hind wings completely fused together so as to 
form a single patch. I propose to call this form connoxa form. nov. (Plate VIII, 
Fig. 2, female). 

16. Ceratinia pellucida. 

(7. pcllacida , Haensch, Berl. Ent. Zeit, L, p. 154. 

Common at the Kaieteur Falls. In the British Museum from Annai and a 
slightly different form from Omai. 

17. Ceratinia barh. 

C. bard , Bates, Trans. Linn. Hoc. XXIII, p. 524 (1862). 

Demerara River ; Omai ; Quonga ; Annai ; Takutu ; Mt. Roraima. 

18. Ceratinia glycon. 

Napcogrnes yhyron , Godman, Ann. Mag. Nat. Hist. 1889, (3), p. 157. 
Annai ; Carimang River ; Takutu ; Potaro River ; Kaieteur Falls, Common 
where found. 

19. Napeogenes oyrianassa. 

Sais n/rianami , Doubleday A Hewitson, Gen. Diurn. Lep. t. 18. f. 1 
(1847). 

Represented iu British Guiana by two forms, adalta Haensch and diluluta 
Haensch ; the former is in the 1 British Museum from Bartica, the Carimang 
River and Esseiiuibo ; the latter from ” British Guiana” 

20. Napeogenes HYGIA. ^Plate VIII, Fig. 1, female). 

N. hygia , Godman, Ann, Mag. Nat. Hist. 1899, (3), p. 157. 

A single specimen was taken on the Upper Kuturi River by G. A. Hudson ; 
the only oxanfple previously known was the type from Paramaribo. 



30 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


tx, 1. 


21. Napeogenes potaronus. 

N. jvtaronus, Kaye, Ent. Rec. XVII, p. 120. 

Poiaro River (W. J. Kaye) ; Kaieteur Falls (A. Hall.) Very rare. 

22. Napeogenes inachia moles. 

N. moh'8, Haensch, Berl. Eat. Zeit. L, p. 157, t. 4, f. 10 (1905). 

Potaro Road ; also in the British Mnseum from “ British Guiana.” 

23. Sais ROSALIA. 

Papilic romhdy Cramer, Pap. Ex. Ill, t. 246, B. (1782). 

Omai ; Demerara River ; Berbice ; Kuturi River. 

24. Sais paraensis camariensis. 

*V. ('((niarirnfii.% Haensch, Berl. Ent. Zeit. L, p. 162, t. 4, f. 12 (1905). 
Described from Camaria on the Cuyuni. There are specimens in the 
British Museum labelled “ Georgetown”. 

25. Scad a theaphia. 

Oleria theaphia , Bates, Trans. Linn. Soc. XXIII, p. 529 (1862\ 

Annai; Quonga; Carimang River; Potaro Road; Kaioteur Falls. Specimens 
from the Potaro Road were described as majascuta Haensch, but I am unable 
to see that they .differ from the typical form. 

26. Dircenna lenea. 

Papilla Jenra, Cramer, Pap. Ex. ID, t. 231, I). (1782). 

Omai; Annai ; Takutu ; Mabaruma ; Mt. Roraima; Kuturi River. At 
Mabaruma I took typical specimens in company with a very pale form 
which has been described as dnxjheda Weeks. 

27. Calloleria nise. 

Papiho ntxe, Cramer, Pap. Ex. Ill, t. 231, E. (1782). 

Annai ; Oinxi ; Ciriming River ; Demerara River ; Mabaruma. Locally 
abundant. 

28. Calloleria cayan\. 

(\ cntjcum, Salvin, Ann. Mag. Nat. Hist. (4), IV, p. 167. 

Potaro River ; Kaieteur Falls. Rare. 

29. Episcada sylph \. 

E. Hj/lphdy Haensch, Berl. Ent. Zeit. L, p. 171 (1905). 

A single specimen from Quonga in the British Museum differs somewhat 
from typical Venezuelan examples and may represent a new iace. 

30. Leucothyris aeolk. 

Papiho aetjlr, Fabricius, Gen. Ins. p. 255 (1777). 

Bartica ; Carimang River ; Potaro River ; Kaieteur Falls. 

31. LljUCOTHYRIS ZAltEPHA. 

* Tthomia zarrpha , Hewitson, Ex. Bull. IV, Ithomia t. 27, t. 173 (1869). 
Demerara River ; Essequi bo River ; Carimang River; Bartica; Kaieteur Falls. 



CATALOGUE OF THE LBPIDOPTERA RHOPALOCERA OF BELTIKH GUIANA. 31 


32. Leucothyrih astrea. 

Pupilio Mirra* Cramer, Pap. Ex. I, t. 22, D. (1775). 

Annai ; Carimang River ; Quonga ; Mabaruma. Generally found singly 
and therefore rare. 

33. Aeria eurimedia. 

Pupilio eurimrdia , Cramer, Pap. Ex. II, t. 126, C.D. (1779), 

Carimang River; Takutu; Kaieteur Falls; Lower Essequibo River; Mabaruma. 

34. PSEUDOSCADA FLORULA EXORNATA. 

P. flora la ab e.roniata, Haenscb, Berl. Ent. Zeit. L, p. 177 (1905), 
Potaro Road. A rare species. 

35. PSEUDOSCADA wana. (Plate VIII, Fig. 3 male). 

P . tvtiau* Hall, “Entomologist” 1930, p. 278. 

Only known from Mabaruma where I took the types in December 1929. 

Family SATYR IDAE. 

36. Callttaera philis. 

Pupilio phi! is* Cramer, Pap. Ex. IV, t. 387, K. (1782). 

Domerara River ; Bartica ; Carimang River ; Mt. Roraiirm. A l’are and 
beautiful species, always found singly. 

37. IIaktera piera. 

Pupilio pirra , Linnaeus, Mus. Fir. p. 220 (1764). 

Demerara River ; Bartica ; Parika ; Carimang River ; Mabaruma ; Kaieteur 
Falls. Not rare in heavy forest. 

38. PlERELLA ASTYOCHE. 

Ilrtarra astyoche, Erichson, Schomb. Reisen III, p. 599 (1848). 
Mabaruma ; Carimang River ; Lower Essequibo River. 

39. PlERELLA LENA. 

Pupilio Iran, Linnaeus, Syst. Nat. I, (2), p. 784 (1767). 

Demerara River ; Bartica ; Carimang River ; Mt. Roraima. Not very com- 
mon anywhere. 

40. PlERELLA DRACONTIS, 

Pirns ( lracontis , Hiibner, Verz. Bek. Schmett. p. 53, n. 500 (1816). 
Common in most wooded places. 

41. PlERELLA LAMIA. 

Pupilio lamia, Sulzer, Gesch. Ins. t. 18, f. 1. (1776) 

Demerara River; Berbice ; Omai; Carimang River; Kaieteur Falls; Mt. 
Roraima. Common where found. 

42. Antirrhaea philoctetes. 

Pupilio philoctetes , Linnaeus, Mus. Ulr. p. 219 (1764). 

Demerara River ; Berbice ; Bartica ; Parika ; Mt. Roraima. Rather scarce 
and difficult to oatch owing to its habit of flying close to the ground in the 
dense undergrowth. 



32 


AGRICULTURAL JOURNAL OF BRITISH GUIANA 


[X, X. 

43. Antirrhaea ornata. 

A. ornata , Butler, Ann. Mag. Nat. Hist. (4) V. p. 3G2. 

A single specimen from Quonga in the British Museum. 

44. Antirrhaea taygetina rodwayi. (Plate VIII, Fig. 8 female). 

A. taygetina rodwayi , eubsp. nov. 

Description. — Differs from typical A, taygdina Bull, in both sexes having 
the postdiscal spots of the hind wings very large and bright blue, 4 to 7 
millimetres in diameter and in the rufous scaling on the outer part of the fore- 
wings being less pronounced. 

Described from two pairs from Anna! and two pairs from “British 
Guiana,” all in the British Museum. 

45. Caerois ohorinarus. 

Papiho cftonnaems, Fabricius, Syst. Ent. p. 484, n. 182 (1775). 

I have taken this fine species at Parika and it is reported from the Demerara 
River, but it seems to be very rare. 

4f>. Taygetis mermeria. 

Papilio menneria, Cramer, Pap Ex. I, t. t)C>, B. (1770). 

A series from Takutu in the British Museum. 

47. Taygetis TjARUa. 

T. lama , Felder, Reise Nov. Lep. Ill, p, 1(50, n. 700 (18(57). 

Takutu; Mt. Roraima. Not a common species. 

18. Taygetis virgtija. 

Papilio virgilia , Cramer, Pap. Ex. I, t. 0(5, C. (1770). 

Not uncommon in shady places, 

40. Taygetib celi a. 

Papiho vet id , Cramer, Pap. Ex. Ill, t. 212, C. (1782). 

There are single specimens from Demerara and Mt. Roraima in tne British 
Museum. 

50. TAYGETTS ANDROMEDA. 

Papilla andromeda , Cramer, Pap. Ex. I, t. Of), A. (1770). 

The commonest species of the genus and, like its allies, fond of the 
shady paths in the forest. 

51. Taygetis xenana. 

7\ xenana, Butler, Lep. Ex. I, t. 7, f. 3 (1870). 

Annai ; Bartica ; Kaieteur Falls. This very dusky species is easily 
overlooked on account of its resemblance to T. andromeda . 

52. Taygetis echo. 

rapilio echo, Cramer, Pap. Ex. I, t. 57, C.D. (1770;. 

Demerara River ; Annai ; Takutu. 

53. Taygetis penelea. 

^ Papilio penelea , Cramer, Pap. Ex. II, t. 101, G. (1770). 

The only specimens I have seen are merely labelled “ British Guiana,” It 
is a very common species in Trinidad. * 



CATALOGUE OP THE LEPIDOPTERA RHOPALOOERA OK BRITISH liUlANA. 33 


54. TAYGETIH VALENTINA. 

Papilio Valentina, Cramer, Pap. Ex. Ill, t. 242, A, (1782). 

Four males from Berbice in the British Museum. It is one of the rarer 
species. 

55. Euptychta hesione. 

Papilio hesione , Sulzer, Geoch. Ins. p. 144, t. 17, f. 3, 4 (1770). 
Generally distributed and very common. 

50. Euptyohia bixocula. 

E. binocula, Butler, Lep. Ex. I, t. 4, f. 5 (1869). 

Found in company with the foregoing but much more local. Bartiea t 
Parika ; Quonga ; Carimang River. 

57. Euptychta ocypete. 

Papilio oei/pete, Fabricius, Gen. Ins. p. 260, (1777). 

Omai ; Annai. 

58. Euptyohia lydia. 

Papilio hjdia, Cramer, Pap. Ex. II, t. 148, C.D. (1779). 

Demerara River ; Annai ; Carimang River ; Kaieteur Falls ; Mt. Roraima ; 
Parika. This species is not very abundant anywhere. 

59. Euptyohia picea. 

E, picea , Butler, Proc. Zool. Soc. 1866, p. 481. t. 12, f. 0 (1807 ) 
Demerara River ; Carimang River ; Bartiea ; Kaieteur Falls. At the latter 
locality I took a remarkable aberration in which the red stripes appear on the 
upperside. 

60. Euptychi \ myxcea. 

Papilio nnjncea, Cramer, Pap. Ex. IY, t. 293, C. (1782). 

Very common and generally distributed. 

61. Euptyohia pexelope. 

Papilio penelope. Fabricius, Syst. Ent. p. 493, n. 217 (1775). 

Another very common species, perhaps more abundant than the preceding. 

62. Euptyohia tkrrestris. 

E. fewest ris, Butler, Proc. Zool. Soc. 1866, p. 462, t. 39 f. 1. 

Widely distributed but less abundant than the two foregoing. 

63. Euptyohia batesii. 

E. batesii, Butler, Proc. Zool. Soc. 1866, p. 493, t. 40, f. 16. 
Demerara River; Carimang River ; Omai ; Kaieteur Falls. A rare species 
only found singly. 

64. EUPT'YCHIA RENATA. 

Papilio renata, Cramer, Pap. Ex. IV. t. 326, A. (1782). 

Common in many localities. Demerara River ; Omai ; Parika; Carimang River. 

65. Euptyohia modesta. 

E. modesta, Butler, Proc. Zool. Soc. 1866, p. 472, n. 42. 

Parika; Bartiea; Carimang River; Not rare but easily overlooked on account 
of its resembftmee to E. renata . 



34 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [X, 1. 

6G. EUPTTCHIA HERMES. 

Pajiilio hermes , Fabricius, Syst. Ent. p. 487, n. 195 (1775). 

Probably the commonest butterfly throughout Tropical America. 
Abundant everywhere and at all seasons. 

07. Euptychia argantb. 

Pajiilio argante, Cramer, Pap. Ex. Ill, t. 201, C.D. (1782). 

In the British Museum from Demerara. 

08. Euptychia liryb. 

Pajiilio lilnjr, Linnaeus, Syst. Nat. I, (2). p. 772, n. 146 (1767). 
Common in forests and undergrowth. 

09. Euptychia gulnare. 

K. guliHiiv, Butler, Ent. Mo. Mag. VI, ]>. 250 t. 1, f. 3 (1870). 

A male from “ British Guiana” in the British Museum. 

70. Euptychia erictho. 

K. erictho, Butler, Proc. Zool. Soc. 1800, p. 501, t. 40, f. 12. 

Oarimang River : Kaieteur Falls ; Mt. Roraima. Common where it occurs. 

f 

71. Euptychia tricolor. 

K. tricolor, Ilewitson, Ann. Mag. Nat. Hist. (2), VI, p. 440 (1840). 
There is a specimen of this rare and beautiful species from the Potaro 
River (H. Roberts) in the collection of W. J. Kaye and one from Demerara in 
the British Museum. Oronoque-New River Confluence (G. A. Hudson). R. 
Snpenaam (coll. Ent. Div. G. Brinsley). 

72. EUPTYCHTA I.EA. 

Pajiilio lea, Cramer, Pap. Ex. II, t. 151, C.D. (1779). 

Berbice: Annai. 

73. Euptychia cephus. 

Pajiilio ce/j/nift, Fabricius, Syst. Ent. p. 528, n. 359 (1779). 

In the Georgetown Museum and in the British Museum from Demerara. 
Fond of dense undergrowth. 

74. Euptychia arnaea. 

Pajiilio droned, Fabricius, Gen. Ins. p. 200 (1777). 

A common species in forests. 

75. Euptychia chlorik. 

Pajiilio chlorhf, Cramer, Pap. Ex. IV, t. 293, A. B. (1782). 

Bartica: Annai; Carimang River. This species and the next arc generally 
found together but are never common. 

70. Euptychta herhe. 

Pajiilio herse, Cramer, Pap. Ex. I, t. 10, C.D. (1775). 

Bartica ; Carimang River ; Annai ; Omai. 

77. SPPTYCHIA TOLUMN1A. 

Pajiilio tot amnia, Cramer, Pap. Ex. II, t. 130. F.G. (1779). 

Single specimens from Berbice and “ British Guiana,” in the British 
Museum. - 



CATALOGUE OB THE LEBlDOPTBRA RHOPALOCERA OP BRITISH GUIANA. 35 


78. Euptychia hewitsonii. 

E. Hewitsonii , Butler, Proc. Zool. Soc. 18C6, p. 491. t. 40, f. 4. 

Bartica ; Annai ; Oarimang River ; Quonga. This curious little species is 
always found singly. 

79. Euptychia cluena, 

Papilio cluena , Drury, 111. Ex. Ent. Ill, t. 7, f. 5, G (1782). 

A pair from Mt. lloraimi in the British Museum. 

80. Bia aotorjon. 

Papilio aclorion , Linnaeus, Syst. Nat. I, (2), p. 794, n. 262, (1767). 
Generally distributed in dense undergrowth. 

Family BRASSOL1DAE. 

81. Brassolis sophorak. 

Papilio sophorar , Linnaeus, Syst. Nat. X, p. 471, n. 83 (1758). 
Common round Georgetown and in most of the coastal districts. The larva 
feeds upon Cabbage Palm and Coconut, clusters of the pupae often being found 
in the spathes. The larvae are much infested by dipterous parasites and when 
they escape these, the freshly emerged butterflies ofteu fall to the ground before 
the wings are fully expanded and so fall victims to ants. 

82. I)YN T \STOR DARIUS. 

Pa pi l to ( lariax , Fabricius, Syst. Ent. p. 482, n. 173 (1775). 

A specimen flew into the rest house at Mabaruma during my stay theie but 
evaded capture. 

83. OPSIPHANES CASSIAE. 

Papilio ctmiw\ Linnaeus, Mas. Fir. p. 2G5 (17G4). 

A single specimen from Deiuerara in the British Museum. 

Si. OPSIPHANES QUITEUIA. 

Papilio (jo Herat, Cramer, Pap. Ex. IV, t. 313, A — I). (1782). 

In the British Museum from Mt. Roraima. 

85. OPSIPHANES IXYlltAE. 

rofttmis saperha invirtte , lliibner, Sam ml. Ex. Schmett. t, 76, f. 1, 2 
(1806-16). 

Demerara : Berbiee ; Mt. Roraima. Probably common in most forest 
regions. 

86. Opsiphanes cassixa meriaxae. 

0 . cassina merianae , Stichel, Berl. Ent. Zeit. XLVI. p. 518 (1901). 
Two females from Demerara in the British Museum. 

87. Catoblepia xanthus. 

Papilio xanthus, Linnaeus, Mus. Fir. p. 276 (1764). 

Demerara River : Bartica. Rare. 

88. Catoblepia berecynthia. 

Papilio berecynthia , Cramer, Pap. Ex. II, t. 181, B.C. (1779). 

Parika ; Bartica ; Carimang River ; Mt* Roraima. 



36 AGRICULTURAL JOURNAL OF BRITISH GUIANA. DC, 1. 

89. Eryphanis polyxena. 

PapiUo polyxcna % Meerburg, Afb. Zeldz. Gen. t. 41 (1775). 

Demerara River ; Takutu ; Mt. Roraima. 

90. Caligo teucer. 

PapiUo teucer , Linnaeus, Mas. Ulr. p. 212 (1764). 

Not uncommon in many places, usually at the edges of cocoa plantations. 
Parika ; Demerara River ; Berbice. 

91. Caligo ilioneus. 

PapiUo iiioneus , Cramer, Pap. Ex. I, t. 52, A. (1779). 

The commonest species of the genus and very generally distributed, the 
larva feeding upon sugar cane. 

92. Caligo eurilochits. 

PapiUo cnrilochus , Cramer, Pap. Ex. I, t. 33, A., A. 34, A. (1775). 
Demerara River ; Friendship on the Berbice ; Takutu. 

93. Caligo idomeneus. 

PapiUo idoinenrus, Linnaeus, Mils. Fir. p. 2J3 (1764). 

Demerara River ; Berbice ; Curimang River ; Kaieteur Falls. 

94. Caligo o'ileus. 

Pavonia oiteus , Felder, Wien. Ent. Mon. V, p. 1 11, n. 1 0C» (186l). 
Marudi Mts., Rupununi District, (L.H.J. Ashburner). 

95. Caligo suz vnna, 

Paroaia s atatnta, Deyrolle, Rev. Zool. 1872, p. 275, JI. 24, 26. 

There are specimens of this rare species in the Georgetown Museum and 
one from “British Guiana” in the British Museum. Demerara (Verity). 

Family MOKPIIIDAE. 

96. Morpho PERSEUS. 

PapiUo persons, Cramer, Pap. Ex. 1, t. 71, A.B. (1779). 

(a). PapiUo mrte/lus . Cramer, Pap. Ex. Ill, 218, A.B. (1782). 

This fine species occurs in two forms both of which are equally scarce. In 
metellus the colour above is golden yellow whilst in prrseto ? it is light blue. 
There are specimens of both forms in the Georgetown Museum and in the British 
Museum from Demerara, and tlio latter institution also has an intermediate 
specimen from the same district. Mackenzie (Verity). 

97. Morpho hecuha. 

PapiUo h&'ubn, Linnaeus, Mant. Plant, p. 531 (1771). 

This is the largest of all South American butterflies and owing to its lofty 
flight it is very rarely captured. I have seen the species filing high above the 
tree** tops at the foot of the Kaieteur Falls and along the Potato Road and there 
are specimens in the Georgetown Museum and in the British Museum from 
Demerara. Mackenzie (Verity). 



CATALOGUE OF THE LEPIDOPTERA RHOPALOCERA OF BRITISH GUIANA. 37 


98. Morpho achtlles. 

Papilio ar/tille.% Linnaeus, Mus. TTlr. p. 211 (17G4). 

The commonest species of the genus. It is found in most wooded places 
and as its flight is lower anil slower than most of the other species it is the one 
most often noticed. It is fond of settling on decaying fruits on the ground and 
will also come to sugar. 

99. Morpho deidami a. 

L/onle drain mat, Hiibner, Verz. Bek. Schmett. p. 52, n. 187 (181G). 
Several at Mabaruma (A. Hall). 

100. Morpho adonis. 

Papilio (/don is, Cramer, Pap. Ex. I. t. Gl, A.B. (1779). 

Mr. W. J. Kaye has S])i*cimenK from the Potaro River. 

101. Morpho rhetenor. 

Pap/ ho rladrnor, Cramer, Pap. Ex. I. t. 15, A.B. (1775). 

The most brilliant of all species on the wing. It occurs rarely on the 
Demerara River and I saw one specimen at the foot of the Kaieteur Falls in 
March. 

102. Morpho mkxelws. 

Paptho menelaa*, Linnaeus, Mus. TTlr. p. 200 0704). 

Next to M. wli/lh**, this is the most widely distributed species of the genus 
and is often common where it occurs, as at Birtica, Mabaruma. on the Potaro 
Road and elsewhere. 


Family NYMPH ALT DAK. 

Sub-family— ACRAEINAE. 

103. ACTTNOTE THVLTA. 

Ptf/nho thaha, Linnaeus, Mus. Vlr. p 2o0(17G4). 

Demerara River ; Berbice ; Takutu. Apparently not very common where 
it is found. 

104. Actinoth ante vs. 

Amaru antra*, Doubleday & Hewitson, Gen. Diurn. Lep. t, 18, f. 5 
(1848). 

A. antra* f. oehrotaeniata , Jordan, in Seitz, Gross.-Schmett. Y, p. 
3(59 (1913). 

There are two pairs of the dimorphic form o/hrotaen/ata from Mt. Roraima 
in the British Museum. 

• Hub-family— HELICONIINEA. 

Before dealing with the forms oi this interesting group it is necessary to 
remark that many species of Helicon i a#, particularly H . melpomrne, H. dor is 
and //. erato are highly polymorphic and have developc d a number of forms 
which have at first sight all the aspect of different species, whilst in other cases 
the influence of mimicry has produced forms of different species which have a 
great similarity to ono another and are sometimes difficult to distinguish. 



38 


AGRICULTURAL JOURNAL OF BRITISH GUIANA* 


[X, 1. 


Mach has been written on this subject by Messrs. Charles Oberthiir, W. J. 
Kaye, H. Eltringham, H. Riffarth, A Seitz and others but unfortunately no 
two authors are quite in agreement in their conclusions. In British Guiarta the 
species are far more constant than is the case in Surinam or French Guiana but 
there are nevertheless a number of interesting varieties whose exact relationship 
can only be eventually proved by breeding. I therefore express no opinion as 
to how far the forms hero recorded are specifically distinct. 

105. Heltconius numata. 

Papilio numata, Cramer, Pap. Ex. IV, t, 297, C.D. (1782). 

A common species in most inland districts but apparently not found close to 
the sea. Lower Essequibo River (Bartioa-Suponaam Forest Survey. In Coll. Ent. 
Div.) Ah. mrlanops Weymer is a common form in which the two black bands 
of the hind wings are confluent. Other aberrations have been named guiensis 
Riffarth and mavors Weymer. 

106. Heltconttts grapattjs thtet/rt. 

H. gradatus thieJri, Riffarth, Berl. Ent. Zeit. XLV, p. 111.") (1900). 

Several specimens from Berbice and Deinerara a,nd two taken by myself at 

Bartica have been placed under this name in the British Museum. It looks very 

much like a further aberration of numata . 

% 

107. Heijcontus euooma. 

Eurides rucoma, Hiibner, Zubr. Ex. Schmett. f.f>77, 578 (182.")). 

A single specimen is recorded by W. .f. Kaye from the Potaro Road. 

108. Hemcontus vetcstus. 

II. vrtustus, Butler, Cist. Ent. I, p. 163, (1873). 

Remerara River ; Bartica ; Berbice ; Potaro Road ; Mabaruma. Apparently 
always rare. 

109. HEUCONIUS 8TLVANA. 

Papi/io silvana, Cramer, Pap. Ex. IV, t. 361, C.R. (1782). 

Remerara River ; Annai ; Potaro Road ; Kuturi River ; Rare and only 
fonnd singly, 

110. HEUCONIUS ETHILLA SULPHURETT8. 

H. sulphurous , Weymer, “ Iris ” VI, p. 311, t. 4. f.8 (1893). 

A specimen from the Barima River in the collection of W. J. Kaye. 

111. HELTOONirS HECALK. 

Papilio hecalr, Fabricins, Gen. Ins. p. 254 (1777). 

(a) H. hrcalr c/rarri. Hall, “ Entomologist ” LX II I, p.278 (1930). 

This is one of the most striking of the butterflies which arc pecnliar to 
British Gniana and is interesting as occurring in two distinct races. Typical 
hecale is locally common near Parika and there are old specimens in the British 
Museum labelled “ Remerara”. The form clearei is only known from a restricted 
spot *at Mabarnma where I discovered it in December 1929. A remarkable 
aberration called Julvoscrns, Lathy, is said to have come from Deinerara but only 
the type specimen is known. * 



CATALOGUE OP THE LEPIDOFTEBA RHOPALOCEBA OP BRITISH GUIANA. 39 


112. Helicontuh tumatttmart. 

H. tumatumari, Kaye, “ Entomologist,” 1906, p. 53. 

Only known from Tumatnmari where it was discovered by W. J. Kaye. 

113. He r. room us melpomenh. 

Papilio molpomme , Linnaeus, Mns. Ulr. p. 232 (1764). 

The typical form is generally distributed and rather common. From 
Parika I have specimens of ah. ntroseda Riffarth in which the red band is partly 
broken up into spots and from Mt. Roraima the British Museum has four males 
and a female of a totally different form near to the one figured in Seitz as eu/alia 
Riff, but with the yellow spots of the fore-wings larger, the males with an 
additional small spot between them. 

114. Heltooniuk aede astydamia. 

11. aulydaima, Erichson, Schomb. Reisen III, p. 595 (1848). 

Demerara River ; Bartica ; Annai : Quonga; Potaro Road ; Takutu. Only 
found singly. 

115. Helioonius xanthoolek. 

H. .raiithoclri, Bates, Trans. Linn. Soc. XXIII, p 561 (1862) 

Demerara River ; Omai ; Quonga ; Potaro Road. Like the preceding 
species it is always rare. 

116. HeLIOONIUK BURNEYT HUBNER1. 

H. buryncyt hurbnen, Standinger, ‘'Iris’’ IX, p. 312 (1896). 

Demerara River ; Omai ; Annai ; Takutu ; Bartica ; Mt. Itoraima. 

117. IlELlCONIUS EGERIA. 

Papilio eyo ia, Cramer, Pap. Ex. 1. 1. 34, B.C. f 1775). 

A single specimen received by W. .1. Kaye from the Totaro Road. It is 
always a rare species. 

118. Heuconics DORIS. 

Papiho <lori«, Linnaeus, Mant. Plant, p. 536 (1771). 

Generally distributed but rarely common at any one place. This species is 
polymorphic but only two forms seem to be at present known from British 
Guiana, namely typical dor id in which the hind wings have a blue band and 
ah. dclila Hubn. with broad red Btreaks on the hind wings. Both forms occur 
together at Annai, Berbice and Mabaruma. 

119. IlELlCONirS CLYTIA FLAVHSCENS. 

H. clytia Jlavedcem, Weymer, Stett. Ent. Zeit. LI, p. 292. 

Parika ; Bartica ; Annai ; Mabaruma. Typical II. chjiia with white bands 
does not seem to occur in British Guiana. 

120. IlEHCONirS WALLACEl. 

H. irallacd, Reakirt, Proc. Ac. Nat. Sc. Phil. 1866, p. 242. 

Annai ; Mabaruma. Closely related to II. clytia and perhaps only another 
form of it. 

121. Heliconius anttochus. 

Papilio antiochus, Linnaeus, Syst, Nat. I, (2), Add. p. 1068 (1 767). 
Demerara River ; Omai ; Quonga : Bartica ; Kamakusa. Often very 
abundant but Uncertain in appearance. 



40 


AC? RICULTUR A L JOURNAL OF BRITISH GUIANA. 


LX, i. 


122, Hblioonius sara rhea. 

Papilio rhea 9 Cramer, Pap, Ex. I, t. 54, O.D. (1775). 

Oae of the most generally distributed species and often abundant. A form 
called ab. brevinnculata Stgr. with the band of the fore-wings broken into two 
spots is found at Mabaruma and probably also elsewhere. 

12I5. Heliconius hydara vtcttlata. 

11. hydara vicuJata , Riffarth, Berl. Ent. Zeit. XLV, p.188 (1905). 

The commonest of the red-banded species of Hr! icon ins, especially in 
districts near the coast. Ab. dryope Riff, with a red stripe at the base of fore- 
wings and ab, coral ii Butl. with the red ban l broken into spots are known to us 
from Annai. 

124. Heliconius erato magntfioa. 

Z7. wrlpomene maynifica , Riffarth, Berl. Ent. Zeit. XLV, p.211, (1005). 
Abundant in many inland districts such as Mabaruma and the Kaieteur Falls 
where it seems largely to replace I'iculata. The form earyas Riffarth from the 
Oarimang River, Annai and Berbice hardly seems to differ. 

125. Eueides rtcini. 

Papilio ncini, Linnaeus, Mus. Dir. p. 227, (17(54). 

Annai. According to Kaye the larva feeds upon ' Cassava as well as on 
Passifiora. 

12(5. Eueides tAles. 

Papilio talri, Cramer, Pap. Ex. I. t. 58, O.D. (177(5.) 

Occurs rarely at Bartica and on the Demorara River. 

127. EUETDES IjAMPETO NTGROFULVA. 

E. ntyrofufra , Kaye, “ Entomologist ” 190(5, p 52. 

Discovered by C, B. Roberts on the Potaro River where it seems to be not 
uncommon locally. 

128. Eueides vibtlia, 

Cethosia vibilia, Godart, Enc. Meth, IX, p. 215, n.CJ (1819), 

Potaro Road. Rare. 

129. EUETDES ISABELLA 

Papilio Isabella , Cramer, Pap. Ex, IV, t. 350, O.D. (1 782). 

Berbice ; Annai ; Potaro Road. Apparently less common than in other 
parts of South America. 

130. Eueides lybia. 

Papilio lybia , Fabricius, Syst. Ent. p. 400, n. 75 (1775). 

Generally distributed in wooded districts and often common. 

131. Euetdes aliphera, 

Cethosia aliphera , Godart, Enc. Meth, IX. p. 240, n, 7 (1919). 

Very common in almost all localities. 

Sub-family— NYMPHALINAE. 

132. Metamorpha dido. 

4 Papilio dido , Linnaeus, Syst. Nat, I, p. 782 (1758). 

A fairly common species, sometimes to be seen even in the streets of 
Georgetown. * The larva feeds upon Passifiora, not Pineapple as stated by 
Madam Meiiam. 9 



CATALOGUE OP THE LBPIDOPTERA RHOPALOCERA OP BRITISH GUIANA. 41 

133. COLAENIS JULIA. 

Papilio julia, Fabricius, SyBt. Ent. p. 509, n. 281 (1775). 

Generally distributed and common. 

134. COLAENIS rHAETUSA. 

Pupil io phaetusa, Linnaeus, Syst, Nat. I, p. 486, n. 123 (1758). 

Locally common, chiefly in swampy districts near the coast. Not rare in the 
Botanical Gardens and other spots near Georgetown. 

135. Dion is vanillae. 

Papilio vanillae , Linnaeus, Syst Nat 1, p. 482, n. 146 (1758). 

Generally distributed and common. 

136. Dione JUNO. 

Papilio jam, Cramer, Pap. Ex. Ill, t. 215, B.C. (1782). 

Generally distributed but not so abundant as I). vanillae. The larva 
likewise lives upon Passifiora. 

137. Epptoieta hkgesia. 

Papilio heyrsia, Cramer, Pap. Ex- HI, t. 209, E.F, (1782). 

In the British Museum from Demerara. Apparently rarer than in most 
parts of South America. 

138. PHYTIOI)S> liimope. 

Papilio I i nope, Cramer, Pap. Ex. I, t.l, C.D, (17/5). 

Generally distributed and often abundant chiefly in the wet seasons. The 
small pale form tlu/iartus Fabr. which occurs at Mabaruma and elsewhere is 
sometimes regarded as a different species. 

139. PllVt'IODES EONTUS. 

P. font as, Hall, "Entomologist” LXI, p. 11 (1928). 

The typo specimen, labelled “ British Guiana” is the only one at present 
known. This crm a from the collection of II. Grose Smith who received most 
of his material from the Essequibo district. 

140. PHYCIODES CLIO. 

Papilio dm, Linnaeus, Syst. Nat. I. p. 167, n.52 (1758). 

Generally distributed and sometimes abundant in or near forests. 

141. Phyciodes nyuplia. 

Papilio nanplia, Linnaeus, Syst. Nat. I, p.448 (1758). 

Demerara Iliver ; Berbice ; Kuturi liiver. 

142 Phyciodes kuniok. 

Nereis fu/va aunice, Hiibner, Samml. Ex. Schmett. t. 9. f.l-i (1806 — 18). 
Generally distributed in forests lmt usually only found singly. Bather 
common near the top of the lvaieteur Falls in March 1936. 

143- Phyciodes aveyrona. 

Eresia aveyrona, Bates, Journ. Ent. II, p. 192 1. 10, f.4 (1861). 

A sing'le specimen in my collection from the Barima River. 

144, CHLOSYNE IAC1WA SAUNDEKSI1. 

Syndilor Saandcrsii , Donbleday A Ilewitson, Gen. Diurn. Lep. t. 24, 
f.2 (1847). 

A specimen in the British Museum labelled “British Guiana, Parish.” It 
is a very common species in Venezuela and in Trinidad. 

(To be continued) 



NEWS. 


Professor J. Sydney Dash, Director of Agriculture, left the Colony for Bar- 
bados on two weeks’ leave of absence on December 24, 1938, returning on 
January 5, 1939. During Professor Dash’s absence Mr. L. D. Cloare, Entomolo- 
gist, was appointed to act as Director and subsequently as Deputy Director. 


Mr. C. LI. B. Williams, Sugar Agronomist and Plant Breeder, returned from 
5 ao months’ leave of absence on January 13 and resumed duty on the same day. 


As from January 1, the following Technical Assistants have been placed 
on the Fixed Establishment : — D. D. Blackman. N. Persand, ('. Williams, 
L. E. McKinnon, A. W. Sears and W. A. Bovell. 


The Director of Agriculture visited Essequibo from January 10 to 13. lie 
was accompanied by Mr. T. Bell who arrived in the Colony on December 13. 
1938, to take up his new appointment as Agricultural Superintendent. Mr. Bell 
has assumed duty in the Essequibo District and Mr. A. A. Abraham has been 
transferred to the Berbice District. 


A Staff Conference was held on January 19-20, when the various pro- 
grammes of district work and experiments to be carried out during 1939 were 
discussed. On the afternoon of the 20th., the Director and Mrs. Dash were “At 
Home ” to the senior members of the staff. 

The Annual General Meeting of the British Guiana Beekeepers’ Association 
was held on January 24. 

A meeting of the Advisory Board of Agriculture was held on January 2.">. 

A meeting of the British Guiana Poultry Association was held on January 
26 and the Annual General Meeting on February 27. 


Mr. E. M. Petcrkin, Agricultural Superintendent, left the Colony on 28 days’ 
sick leave on January 28, returning on February 21. 


In July last year a Royal Commission was appointed “ to investigate social 
andxconomic conditions in Barbados, British Guiana, British Honduras, Jamaica, 
the ^Leeward Islands, Trinidad and Tobago, and the Windward Islands, and 
matters connected therewith, and to make recommendations ’’. This Commission 



NEWS. 


43 


arrived in British Gniana on January 27, visited several districts and held public 
hearings from January 30 to February 23. The Director of Agriculture gave 
evidence on February 2. 

Professor F. L. Engledow, the Agricultural Expert on the Commission, 
visited the Head Office and the Divisions of the Department on several occasions, 
and the East Demerara and Berbice Districts from February 21 to 23 with the 
Director of Agriculture. The Director of Agriculture also accompanied the 
Commission on a visit to the Essequibo Coast from February 2 to 4. 


The Director of Agriculture has been appointed Chairman of a Committee 
“ to enquire into and advise on the feasibility of establishing one or more-Dairy 
Products factories and to furnish estimates of the capital and recurrent expendi- 
ture of such a factory or factories ”. The other members of the Committee are 
Hons. J. I. D’ Aguiar, C. R. Jacob, A. G. King, C. V. Wight, B.A., T. Lee, Dr. A. 
Fulton, Messrs. R. V. Evan Wong, B.Sc., and H. A. Fraser, B.V.Sc. (Acting 
Government Veterinary Surgeon). 


Dr. D. W. Duthie, Chemist, has been attached in an advisory capacity to an 
International Commission appointed to investigate the possibilities of settlement 
of Jewish refugees in British Guiana. The members of the Commission are 
Dr. E. C. Ernst (Chairman), Col. H. U. Nicholas, Dr. J. A. Rosen, Mr. E. C. Bataille, 
Dr. A. Donovan, Sir Geoffrey Evans, Sir Crawford Douglas-Jones and Mr. D. 
Holdridge (Secretary). 


Mr. II. Parker, General Manager of Government Rice Mills, Federated 
Miley States, who was detailed to investigate the possibility of the erection of a 
central rice mill in Essequibo, and generally to consider rice milling problems in 
the Colony, has submitted his report to Government. This report has been 
published as Legislative Council Sessional Paper No. 3/1939. 


The report of the Committee appointed to report on matters connected 
with the establishment of a rice mill on the Essequibo Coast has been published 
as Legislative Council Paper No. 4/1939. 


Mr. E. R. Campbell, a principal of Messrs. Curtis Campbell & Co., Ltd., 
visited the Head Office and the Sugar Experiment Station on March 3. Other 
visitors included Dr. E. C. Ernst, Dr. J. A. Rosen and Sir Geoffrey Evans, mem- 
bers of the Commission on Jewish settlement. 


Agriculturists generally will regret that His Excellency Sir Wilfred Jackson, 
K.C.M.G. will be leaving the Colony shortly on medical advice. It is announced 
that His Excellency the Governor of Barbados, the Hon. E. J. Waddington, 
C.M.G., will adnfinister the Government in the interim. 



PLANT AND SEED IMPORTATION. 


Introductions by the Department of Agriculture for the period 
November, 1938 to February, 1939. 


Name 

Quantity. 

Whence Supplied 

Economic. 



Girigiri —Vigna oniata 

i oz. 

Agricultural Department. 
Zaria, Nigeria. 

Tobacco Seed 

5 oz. 

Coker*B Podigreed Seed Co., 
Hartsville, S.C. 

Cinnamonum zelaniam 

3 oz. 

Curator, Royal Botanic 

Gardens, Dept, of Agricul- 
ture, Trinidad. 

Cucumber — 3 varieties 

£ oz. each 

1 Messrs. Ferry-Morse Seed Co., 
California. 

Pepper — California Wonder 

do. 

do. 

Egg Plant— Black Beauty 

do. 

do. 

Muskmelon — 4 varieties 

1 do. 

do. 

Watermelon^ varieties 

do. 

i 

do. 

Squash— 2 varieties 

do. 

do. 

Tomato — 3 varieties 

1 do. 

do. 

Cane Cuttings — 7 varieties 

cuttings of each 

Plant Quarantine Station, 

Dept, of Agriculture, 
Trinidad. 

Lespedeza — 5 varieties 

£ oz. each 

Messrs. S. H. Robertson & Son, 
Northumberland Co., 
Virginia, 

Camongay — M ori nga ole if era 

4 lb. 

ITnhersity of Hawaii, 

! Honolulu, Hawaii. 

Rice — 4 varieties 

2 oz. each 

Rice Breeding Station, 

1 Karjat (Kolaba), India. 

Rice— *4 varieties 

Samples of each 

l 

Asst. Paddy Specialist, Rice 
Kxpt, Station, Nagiua,N,P., 
India. 

Ornamental. 


i 

Makita Nut —Farniartum laurinum 

1 lb. 132 oz, 

Director of Agriculture, Fiji, 

Ivi Nut or Tahitian Chestnut— 

1 no car pus edulis 

do. 

do. 

Flower Seeds 
h 

i lb, 

Messrs. Hurst & Son, London. 



METEOROLOGICAL DATA, 1938. 


BOTANIC GARDENS, GEORGETOWN. 


1938 

Rainfall, 


Number of Days of 

Rain 






1 * 

i ~ . 

. 

Evapora- 

Months 

Inches 

S fl 

0 © 
0*1 

.10 in 
to 

.50 in 

.50 in. 
to 

1.00 in 

1.00 in 
to 

2.00 in 

Above 
2.00 in 

Total 

Days 

tion. 

Inches 

January 

13.34 

4 

7 

3 

6 


20 

3.86 

February 

13.10 

\) 

6 

2 

3 

2 

22 

3.51 

March 

13.76 

9 

6 

1 

4 ! 

2 

22 

4.47 

April 

7.95 

4 

5 

7 

2 


18 

4.17 

May 

11.17 

5 

15 

6 

2 

... 

28 

4.12 

June 

13.17 

4 

12 

6 

4 i 

... 

26 

3.92 

July 

1 12.74 

7 

s 

4 

1 , 

2 

22 

4.12 

August 

14.96 

6 

7 

4 

3 

2 

| 22 

3.86 

September 

1.83 

3 

3 

i 


• • • 

7 | 

5.60 

October 

3.48 | 

3 

4 

1 

i 


9 

5.31 

November 

5.12 

4 

4 

2 


i 

11 

4.18 

December 

6.36 

8 

6 

1 

3 

... 

18 

4.27 

Totals 

119.00 

1 

66 

83 1 

f 

38 

29 

9 

225 

51.39 


AIR TEMPERATURE AND HUMIDITY IN THE SHADE. 

BOTANIC GARDENS, GEORGETOWN. 


Months 

Air Temperature 

Humidity 

Mean 

Maximum 

Minimum 

Mean 

January 

84.1 

75.6 

79.8 

82.5 

Febrnary 

83.7 

• 86.5 

80.1 

85.3 

March 

83.5 

75.7 

79.6 

82.9 

April 

84.4 

76 3 

80.3 

82.0 

May 

84.9 

76.2 

80.5 

84.8 

Jane 

84.5 

75.3 

79.9 

84.3 

July 

85.1 

74.9 

80.0 

83.6 

August 

86.3 

75.0 

80.6 

83.5 

September 

88.2 

76.8 

82.5 

80.0 

October 

88.2 

76.4 

• 82.3 

78.9 

November 

87.3 

76.9 

82.1 

81.4 

December 

85.5 

75.6 

80.5 

*82.2 

Mean 

85.5 

75.9 

80.7 

82.6 


WETTEST AND HOTTEST DAYS AT VARIOUS . STATIONS. 


Stations 

Wettest 

Days 

Botanic Gardens, 
Georgetown 

... ^ . 

Feb. 11th 

New Amsterdam, 

May 6th 

Public Gardens 

Ouderneeming Indus- 
trial School, Essequibo 

March 16th 

Hosororo, 

N.W.l). 

Feb. 14th 


Rainfall, 

Inches 

1 Hottest 

1 Days 

Temperture 

in 

shade °F 

4.31 

1 Oct. 27th 

1 ! 

91.0 

i 

1 

3.92 

i 

1 Sept. 2nd 

.1. 

94.0 

j 

6.39 

Nor. 8th, 
9th, 10th 

, 91.0 

1 

3.40 

Aug. 10th 
Sept. 10th 

92.5 









VoL X, No. 2. 


June, 1939. 


The 

Agricultural Journal 

Of 

British Guiana 



PUBLISHED BY 

THE DEPARTMENT OF AGRICULTURE 

GEORGETOWN, BRITISH GUIANA 


Price 


•• 

M 


• « 


• • 
• f 


6d. 




DEPARTMENT OF AGRICULTURE. 

ADMINISTRATION 


Director of Agriculture 
Deputy Director 

Clerical 

Senior Clerk 
Registrar of Banks 


Class III Clerks 


Probationers 


Librarian 

RESEARCH BRANCH. 

Botany and Plant Pathology 

Botanist — Plant Pathologist and Superintend - 
ent, Botanic Gardens : 

E. B. Martyn, B.A., A.I.C.T.A. 

Technical Assistant: 

N. Persaud 

Chemistry 

Chemist : 

D. W. Duthie, M.A,B.Sc„ Ph.D., F.I.C. 

Assistant Chemist : 

C. L. C. Bourne (on leave) 

Economics 

Agricultural Economist : 

H. D. Huggins, M.Sc., Dip. Agr. 

Entomology 

Entomologist : 

L. 1>.‘ Cleare, F.R. Ent. S. 

Technical Assistant : 

C. Williams 

Rice 

Assistant Plant Breeder : 

P. A. ChanCboong, B.Sc., A.I.C.T.A. 

Sugar 

(In co-qperation with the Sugar Producers) 

Sugar Agronomist and Plant Breeder : 

C. H. B. Williams, M.A., A.I.C.T.A., Dip. 
Agr. 

Laboratory Assistants : 

H. B. Singh 

A. V. Wan-Ping, Dip. Agr. 

Statistical Assistant : 

J. B. Bourne, F.S S. 


Prof. The Hon. J. Sydney Dash, 

B.Sc. (Agric.) 

... (vacant) 

L. D. Cleare, F,R, Ent. S. (acting) 

Staff. 

J. F. Irving, M.C. 

W. G. Delph (on leave) 

A. A. Thorne (acting) 

C. A. Lashiey (acting) 

Miss D. M. Terrill 

Miss M. Cheong 
P. 0. Jackson 
-J S. A. Adams 
I Mi as S. Lord 
' Miss B. Delph 

Miss Y. Chan-Choong 

LIVESTOCK BRANCH 

Veterinary Surgeon : 

Vacant 

H A Fraser, B Y Sc. (acting) 

FIELD BRANCH 

Agricultural Superintendents : 

Berbice— A. A. Abraham 
Demerara, East— E.M. Peterkin 
Demerara, East Bank— H. D. Huggins, 
M.Sc., Dip. Agr. 

Demerara. West — E. G. Benson, B.Sc., 
A.I.C.T.A., Dip. Agr. 
Essequibo-T. Bell, B.S.A., A.I.C.T.A. 

Assistant Agricultural Superintendent: 
Berbice— E. M. Morgan 

Agricultural Instructors : 

Berbice — 0. F. J. Churaman, Dip. Agr. 
Botanic Gardens — H. A. Cole 
Demerara. East— 0 C. Dowding, F.L.S,. 
F.R.H.S. 

A griculiural A ssixtants : 

Demerara, East — J. Indrobeharry 
Essequibo — H. B. France 

Technical Assist ants : 

Demerara, East— W. A. Bovell 

Essequibo — A. W. Sears 

North West District— L. E. McKinnon 

Sugar 

Field Manager (Central Station) 

C. Cameron 

Field Assistants : 

L. A. Fmrte 
B. A. McArthur 



METEOROLOGICAL BRANCH 

Technical A instant i 
D. D. Blackman 

Meteorological Assistant : 

J. E. Isaacs 


RICE GRADING BRANCH 

Grading Inspector : 

H. E. H. Gadd 

Technical Assistants : 

B. R. Boss 
G. L. Leitch 


ADVISORY BOARD OF AGRICULTURE 

Director of Agriculture, Chairman, ex officio . 

Deputy Director of Agriculture, Vice-Chairman, ex officio . 

Hon. Peer Bacchus ... ... ... \ 

Hon. R. E. Brassington ... ... ... ) 

Hon. J W. Jackson ... ... ... [ 

Hon. F. J. Seaford, o.b.e ... ... ... > Members 

Mr. S. Andries ... ... ... ... I 

„ B. B. Hunter ... ... ... 1 

„ W. H. Richards ... ... ... ' 


SUGAR EXPERIMENT STATIONS’ COMMITTEE. 


Director of Agriculture, Chairman, ex-officio. 
Hon. M. B G. Austin, o.b.e. 

Mr. G. M. Eccles 
„ J. C. Gibson 

„ A. Murison 

„ L. Lywood (acting for Mr. R. E. Rhodes) 
„ J. Bee 


Georgetown 
Pin. Blairmont 
Messrs. Booker Bros. 

McConnell Co. Ltd. 
Pin. Uitvlugt 
Pin. Leonora 
Pin. Albion 


Represeattaf 
the Sugar 
Industry 
which naia- 
talas the 
Statioas 


CO-OPERATIVE CREDIT BANKS’ BOARD. 


Director of Agriculture, Chairman, ex-officio. 
Hon. J. W. Jackson 
Rev. A. E. Dyett... 

Mr. 0. Farnum 
.. J.L. Wills ... 


Members 


DISTRICT AGRICULTURAL COMMITTEES 


EAST DEMERARA 


Director of Agriculture, Chairman 

District Commissioner 

Deputy Director of Agriculture 

Hon. J. I. deAgukr 

Hon. E. M. Walcott 

Mr. S. Andries ... 

... \ 


Members 

„ M. Ghani 
., W. H. Richards 
„ J.E. Wills ... 

J 



WEST 

DEMERARA 


Director of Agriculture, Chairman 

District Commissioner 




Deputy Director of Agriculture 

Hon. J. W. Jaokson 

Dr. the Hon. J. B. Singh 

Mr. R. P. Carryl 
,. J. C. DaSilva 
„ B. Hunter 

:: ' 

» 

Members 

>. A. Murison ... 




„ W. Ramdeholl 
n A. Rayman ... 





CONTENTS 


(VOL. X, No. 2.) 

Page 

EDITORIAL— 47 

BERBICE COUNTY EXHIBITION— 49 

ORIGINAL ARTICLES. 

The Amazon Fly {Met agon - 
isti/lum minense, Towns.) 

in British Guiana ... L. D. Cleure, F.R.Ent.S. ... 55 

Testing Large Numbers of 
Rice Varieties by the 

Quasi-Factorial Method ... P. A. Chan-Choong, B.Sc., A.I.C.T.A. 78 

Double versus Single Plant- 
ing of Sugar-cane ... C. H. B. Williams, M.A., A.I.C.T.A. , 

Dip. Agr. and 

L. A. Forte ... ... ... 89 

Catalogue of the Lepidophra 
rhopalocera (Butterflies) 

of British Guiana. (Could.) ... Arthur Halt, F.R.Ent.S. ... 96 

NOTES. 

The Foreshore Vegetation 

East of Georgetown ... ... ••• ••• ••• 105 

Plant Inspection Service ... ... — ••• ••• 10? 

PLANT AND SEED EXCHANGE ... ... ... * ... 108 

METEOROLOGICAL DATA ... ... ... ... 110 



Contents — Continued. 

ILLUSTRATIONS 


Facing Page 


Plate 

I. — Fig. 

1 — The Amazon Fly, Metagonistylum mineme 
Towns, x 6. 

56 

»y 

Fig. 

2 — Sugar-cane Moth-borer Investigation 
Laboratory, 1931-35, at Sugar Experiment 
Station, British Qniana 

56 




Page 


Fig. 

1 — Sketch of Sixtus photo-electric exposure 
meter showing intensity of light at which 
matings of Metagonixtyluin occur 

62 



Facing 

Page 

Plate 

II. — Fig. 

1 — The Seaward Edge of the Courida at 
Liliendaal 

106 

»* 

Fig. 

2— Rice Grass West of Kitty Jetty, May, 1939 ... 

106 



The 


Agricultural Journal of British Guiana. 

June, 1939. 

EDITORIAL. 


SELF-SUFFICIENCY. 

Few movements are affecting modern agriculture more than the world 
wide trend towards self-sufficiency. The arguments for and against this move- 
ment are no longer heard as often as formerly, because the concept, whether 
or not approved in principle, must in most cases be given effect to in practice. 

An illustration of cause and effect of this self-sufficiency movement is 
given by the world rice trade. There has been, within the last ten years, a great 
increase in the production of this crop in several major importing countries 
which have been compelled to regulate their imports in the interest of national 
economy. Such development has been particularly marked in the raw material 
exporting countries of the far East and South America. Thus when Malayan 
exports of rubber and tin were high, rice imports were large; as exports of 
rubber and tin fell during the world depression unemployment resulted and rice 
imports declined. In recent years, several of the Governments of South 
American countries — notably Argentina, Colombia and Peru — have increased 
rice import duties in order to increase .home production. In Brazil extensive 
loans to rice growers, the systematic employment of rice specialists and other 
large scale spending programmes, have done much to increase domestic output. 
Such have been some of the causes inducing self-sufficiency in rice and the 
results have been equally subtle and far-reaching. Those countries which pre- 
viously supplied the world’s markets with rice are meeting with a curtailed 
demand. It is clear that these countries will, in turn, have their income 
restricted and so must themselves resort to self-sufficiency in one direction or 
another. Thus the vicious circle continues and it is in this situation that 

British Guiana with many other countries of the world finds itself today. 

* 

When an agricultural exhibition was held in British Guiana recently it was, 
therefore, not surprising to observe that a focus of attention was the indication 
given by the exhibition in regard to the Colony’s self-sufficiency development. 



48 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


[X, 2. 


The exhibition was held in New Amsterdam, Berbice, on Friday and Satur- 
day, April 21 and 22. In spite of heavy rains causing flood conditions in 
many areas shortly before the exhibition, an excellent collection of agricultural 
exhibits of all kinds were on show. His Excellency the Governor, Sir E. J. 
Waddington, K.C.M.G., O.B.E., put into words the view of everyone when he 
emphasized how surprised he was at the fine display of exhibits which he had 
seen in the various stands “ despite the very abnormal weather conditions.” 
Elsewhere in this Journal is given an account of the Exhibition, where it 
will be seen that special mention was made of what is being achieved in regard 
to making the Colony more self-sufficient. The Director of Agriculture said : 
“The general display of garden produce is worthy of mention as it shows the 
great interest taken in the movement towards self-sufficiency, and Berbice in the 
past has been rather behind in this respect. This I feel reflects credit on 
the growers and I am sure the advantages of the Agricultural Bias scheme are 
becoming apparent”. 

The Berbice County Exhibition was in every way a great success, as was 
its predecessor in Georgetown, the Jubilee Agricultural Exhibition. In British 
Guiana, it is still a formidable task to organize and' bring to a successful con- 
clusion projects of this type, but with each success the task is reduced. It is 
evident that 'in this Colony there is now being built up, surely, if slowly, an 
exhibition tradition which provides the chief urge for co-operation between the 
several classes and interests in the community. 

An agricultural exhibition is helpful in many ways. The producer gives of 
his best and sees by comparison how his best can be made better; the public 
takes away impressions which, by attracting attention to home grown products, 
makes it easier for the Colony to expand its self-sufficiency programme. 



BERBICE COUNTY EXHIBITION. 


The Berbice County Exhibition was held in Colony House Gardens, New 
Amsterdam, Berbice, on Friday and Saturday, April 21 and 22, 1939. The 
Exhibition took place after having been postponed on three previous occasions 
and even on the day previous to the date finally fixed, continuous rains 
threatened to compel abandonment. Not only did weather on the 21st turn out 
to be fine but agricultural products of all kinds poured into the exhibition 
grounds in quantity. It was only on the morning of the day itself that the 
Organizing Committee realized what a great success the exhibition was. It 
could be seen, from early in the day, that visitors to the show who came to be 
entertained, remained to be impressed. 

Exhibits were invited under the 12 following classes : 

1. Sugar Cane (open to cane farmers) ; 2. Rice; 3. Livestock; 4. Coconuts: 
5. Coffee; 6. Provision Crops; 7. Vegetable Crops; 8. Fruit; 9. Cacao; 10. 
Miscellaneous Crops; 11. Home Manufactures; 12. Beekeeping. 

Seven stands were erected. One stand, reserved for the various Divisions 
of the Department, displayed exhibits of an educational nature. A special 
feature of this stand was the use of diagrams, models and simple means of 
illustration to render the propaganda efforts as effective as possible. A 
separate stand, faced with split sugar canes, prepared by the Sugar Experiment 
Station, contained educational exhibits relating to sugar production. In 
addition, there were three large stands to house competitors’ agricultural 
exhibits and two for livestock entries. In certain classes so many articles were 
received that they had to be placed on the ground near to their respective 
booths. It is estimated that 5,000 persons visited the exhibition and that 
approximately 1,000 exhibits were on view. 

In the sugar educational exhibit, several diagrams bearing on the different 
aspects of sugar-cane cultivation and the inter-relationship of the industry 
with the Colony’s economic structure were on view. During the last decade 
the Colony’s yield of sugar per acre has approximately doubled; different 
varieties and diagrams relating to the cultural practices which have brought 
this about provided the public with a good deal of useful information. The 
Berbice sygar estates co-operated by exhibiting clumps of cane varieties and 
samples of manufactured products. 

In the rice section, a wide range of padi and rice samples helped to give 
the grower an impression of the various considerations to be borne jn mind in 
regard to different varieties. There were also diagrams in connection with 
the rice breeding work showing the variety status and the progress in the estab- 
lishment of pyre line areas. 



50 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


EX, 2. 


In the entomological section, the chief feature was a series of large posters 
showing in colour the different stages in the life history some of the Colony’s 
important pests together with control measures. Specimens of the Amazon fly 
in a breeding cage helped to give an indication of the method that has been, 
found effective in rearing this fly in sufficient numbers to reduce the damage 
caused by moth borer to the present level. Several types of spraying machines 
were on view. 

In the horticultural and plant propagation section plants of economic value 
formed a special feature together with demonstrations relating to the methods 
to be adopted in budding and grafting. Various simple hints in regard to 
nursery practices were also given. A special tobacco demonstration showing 
the different stages in the production of the crop up to and including the curing 
stage appeared all the more realistic with the inclusion of a model tobacco barn. 
The barn was made to scale and included flues, wires for hanging and even 
small tobacco leaves. 

The chemistry section illustrated various features of soil work, including 
soil-less culture of vegetables and flood fallowing, and demonstrations in con- 
nection with parboiling and rice processing. < 

Standardised beekeeping equipment was shown with the object of drawing 
the attention of rural beekeepers to the advantages obtained from modern 
practice and appliances. 

An effort was made in the economics section to indicate by diagrams some 
of the chief trends in economic progress during recent times. Attention was, 
for example, drawn to the remarkable expansion in the exports of cattle and 
poultry to Trinidad within the last three years. 

Leaflets especially those which would be considered of practical application 
to the farmer were on show and distributed to those interested. 

The Department of Agriculture is indebted to the Exhibition Com- 
mittee for the assistance given in connection with organization arrangements 
Members of the Committee were : 

Members of the Advisory Board of Agriculture with 

Hon. J. Eleazar, Mayor of New Amsterdam 

Hon. E. A. Luckhoo, O.B.E., 

District Commissioner, Berbice, 

Messrs. G. M. Eccles, H. F. Chapman, F. F. Ross, Jas. Bee, J. C. Gibson, 
S. J. F. Blanchard, T. P. Jaundoo, C. Farrar, II. T. King, J. Haly, Rev. 
A. E. Dyett, Canon Gregory and the Agricultural Superintendent, 
Berbice. 

Thanks are also due to the Militia Band which was in attendance on both 
days. 



BERBICE COUNTY EXHIBITION. 


51 


The following is an account of the opening ceremony : 

DIRECTOR OF AGRICULTURE'S REVIEW 

Your Excellency, 'Your Worship, Ladies and Gentlemen : — I speak on behalf 
of the Berbice Exhibition Committee. My most important duty to-day — and it 
is a real pleasure, Sir — is to welcome warmly Your Excellency and Mrs, 
Waddington; I will not say to New Amsterdam as that would be stealing the 
Mayor’s thunder and I am sure he will wish to do that himself. 

As agriculturists we are glad to have you once more amongst us, and we 
do know that Barbados has spared you most grudgingly, in spite of the fact that 
Barbados frequently claims British Guiana as a daughter Colony. Feelings 
have been a little strained recently because we have had the impudence to claim 
that we could rival her in the production of that delectable table delicacy — the 
sweet potato. Anyhow, Sir, we hope when you return you will be able to say 
that the claim is abundantly justified. 

Now, this Exhibition, like most others with which I have been acquainted 
in this Colony, has not been without its vicissitudes. Planned to take place 
originally in 1937 it was postponed to April, 1938, on account of labour troubles 
in the Colony; unfortunately prolonged excessive rains caused a further post- 
ponement to April, 1939. Then it had to be deferred for one week on account 
of the recent abnormal rains. 

Looking back to previous records I find that April has usually been asso- 
ciated with Exhibitions although some have been held in the summer months. 
The 1935 Jubilee Exhibition which was most successful was an April Show. 
April is a good month because it is possible to stage practically everything 
grown in the Colony at this time of the year. 

Coming more particularly to the display before you I think it will be 
admitted that it is most gratifying — the stands are laden with good things and 
would have been fuller still if the floods had not destroyed many ground pro- 
vision areas, especially on the West Coast, Berbice, but the Committee felt that 
to go on postponing the Show could only have resulted in great discouragement 
and dissatisfaction to the majority of farmers. I must say that it is a source 
of great satisfaction to note the keenness and enthusiasm generally. Much of 
the detailed work has been carried out by my Berbice staff led by the Agricul- 
tural Superintendent, Mr. Abraham, east of the river, and Mr. Morgan, west of 
the river. Their labours have been justified by the results. It is hoped to 
run special competitions in the affected areas to aid their re-establishment. 

I do not wish to detain you at any length, but I must refer to one or two 
special features. The general display of garden produce is worthy of mention 
as it shoMrs the great interest taken in the movement towards self-sufficiency 
and Berbice in the past has been rather behind in this respect. This I feel 
reflects credit on the growers and I am sure the advantages of the Agricultural 
Bias scheme are becoming apparent. In this connexion I wish to mention par- 
ticularly the splendid efforts of Mr. Fraser, Head-Master of Friends Scots 
School, who was one of the first batch of teachers turned out by the Agricul- 
ture Department. I will read you what Professor Engledow wrote in his school 



52 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [X, 2. 

log-book after seeing him at work with his boys whom he asked many questions 
and from whom he received satisfactory replies : 

“ 15.2.39. I found the garden well managed. The boys had a far better 
understanding of the cultivation and management of the land than I have 
usually found in schools I have visited in the Caribbean. The teaching should* 
be of good value in a district in which food and vegetable crops are grown.” 

(Sgd.) F. Engledow, 
West India Royal Commission. 


Mr. Fraser has been awarded the Cup presented by the Royal Bank of 
Canada.' 

I cannot refrain also from mentioning the minor crop efforts of Mr. 
Blanchard, Pin. Lochaber. He has been persevering for some time now with 
tobacco and tomatoes, and encouraging his tenants to improve their livestock. 
The heavy rains have dealt him a great blow but he is not discouraged and it 
gives me great pleasure to announce him the winner of the Cup presented by 
Barclays Bank for his initiative and enterprise. 

While on the subject of tobacco which is receiving increased attention as a 
result of the recent demonstration by local cigarette factories, I would direct 
your attention to the educational exhibit in the Department’s stand. It depicts 
the stages of cultivation right through to curing by heat and there is a model 
flue barn, the work of Mr. MacArthur, one of our subordinate staff. 

I will not say much of Sugar and Rice. Progress in these industries is 
well known and they are fully represented on this occasion. The Sugar stand is 
splendid and the staff of the Experiment Station have done good work. 

In connexion with Rice efforts in Berbice I am pleased to announce the 
award of His Excellency the Governor’s prize of $10 to Mr. Ramjohn. Please 
do not fail to see Mr. Ramjolin’s exhibits. 

Another effort which is being specially rewarded is that of the Mental 
Asylum where very useful work is being put in on vegetable and fruit-growing. 
My own humble prize of 1,000 local cigarettes will be handed over to the Medical 
Officer in charge for distribution to the men who have supplied a number of 
exhibits. 

The exhibits in the Livestock section, Home Manufactures and Fruit have 
all reached a high standard but time will not permit any detailed mention. 

I hope you will devote some time to the educational exhibits put up by tho 
Department of Agriculture. A visit to the stand will repay you. 

* It is customary at this stage to announce the winners of the Diploma of 
Merit awarded by the Department of Agriculture for exhibits of outstanding 
merit but the list is not yet complete and will be published later. 



BERBICE COUNTY EXHIBITION. 


53 


Finally, I desire to tnank from the bottom of my heart all those who have 
contributed in any way to the success of the Exhibition, especially farmers and 
cattle-raisers who have suffered great hardship recently. 

I now have much pleasure in asking Your Excellency to open the Exhibition. 


H.E. THE GOVERNOR OPENS EXHIBITION 

His Excellency said that he was very surprised at the fine display 
of exhibits which he had seen in the various stalls. He was told that about 12 
years ago an exhibition was held in New Amsterdam during the regime of His 
Excellency Sir Cecil Hunter Rodwell and though that one was of a very high 
standard this exhibition, despite the very abnormal weather conditions he was 
told, was not one whit behind. 

He congratulated Mr. W. A. Fraser of whom Professor Engledow had 
spoken so highly on having annexed the beautiful silver trophy presented by the 
Royal Bank of Canada for his fine display of garden produce. He also congrat- 
ulated Mr. Blanchard who won the Cup presented by Messrs. Barclays Bank for 
his initiative and enterprise. He also thanked the Mayor and Town Council 
for the help they had given and also Professor Dash and his Staff for all that 
they had done. 

The Hon. J. Eleazar, Mayor of New Amsterdam, in thanking His Expel- 
lency for coming to declare the show open, made reference to the abnormal 
weather conditions and the need for proper drainage for farmers. Despite the 
weather, however, they were able in two weeks to bring off a fine exhibition. 
He thanked all those who had helped to make the show a success. 

Mrs. Waddington presented the Cups to the winners with whom she shook 
hands and whom she congratulated. She was presented with a beautiful 
bouquet by little Miss Cynthia Harrington. 

His Excellency thereafter declared the exhibition open. 


DIPLOMAS OF MERIT. 

An announcement has since been made of those exhibitors who have been 
awarded Diplomas of Merit. The list is as follows : — 


Name 

Ramjohn, Corentyne 

Rash Beharry & Co., Essequibo 

Rev. A. E. Dyett, Corentyne 


Exhibit 

Long grain padi and rice — Demerara 
Creole Variety. 

Whole grain super rice packed for 
export — Blue Stick variety. 

Holstein Bull, 


Harold Ramdehpll, New Amsterdam Capons. 



agricultural Journal of britIsh guIaNA. 


U 

Auchlyne Scots School, Whim, Cor- 
entyne 

Friends Scots School, E.B., Berbice 
River. 1 

No. 5 Congregational School, W.C., 
Berbice 

Henry Chan, Rosignol, W.C., Berbice 

Plantation Providence, Berbice 

Emily Collins, Golden Grove, E.C., 
Demerara. 

Cecilia Robinson, Enmore Front, 
E.C., Demerara. 

Domestic Science Centre, New Am- 
sterdam, Berbice 

Georgetown Prison 

British Guiana Broom Factory, 
Georgetown. 


tx,a. 

School Garden Produce. 

School Garden Produce. 

School Garden Produce. 

Grapefruit — produce of Pin. Plegt 
Anchor, Berbice River.' 

Limes and lime products. 

An assortment of meals. 

An assortment of meals. 

f 

An assortment of preserves. 

Fibres, Ropes and Mats. 

Brooms. 



ORIGINA L AR TICLES. 

THE AMAZON FLY ( ME TAGONISTY L UM MINENSE, 
TOWNS.) IN BRITISH GUIANA* 

By L. D. CLEARS, 

Entomologist , Department of Agriculture , British Guiana . t 

Contents. 

PAGE 


1. History of the project 55 

2. Introduction of the parasite 5fi 

3. Bionomics 58 

4. Species of Diafraea attacked 65 

5. Colonisation in British Guiana ... ... 66 

6. Cost of introducing the parasite 72 

7. Parasitism of D . xarcharalix in rice and other host-plants 72 

8. Status in 1937 73 

9. Shipments of the parasite to the West Indies 75 

10. Acknowledgments 76 


1. History of tiie Project. 

In 1932 on an expedition in Brazil, Dr. J. G. Myers, of the Imperial 
Institute of Entomology, while in search for suitable parasites for introduction 
into this and other colonies in the West Indian area, discovered the Tachinid fly 
Metagonistglum minense. Towns., known generally now as the Amazon fly, as 
an important parasite of Diatraea saccharalis , F., in the vicinity of Santarem on 
the Amazon, and as the result of his investigations there, formed the opinion 
that it would be a suitable parasite for introduction into British Guiana. 

On his return to British Guiana in January 1933, Dr. Myers acquainted the 
Sugar Producers’ Association of this Colony of his discovery, and suggested the 
utilization of the parasite in the cane-fields of British Guiana. The Association 
undertook to bear the cost of the introduction of the parasite and provided a 
sum of £2,000 for this, the fund being administered by the Director of 
Agriculture. 

In May 1933 Dr. Myers, accompanied by Mr. A. H. Pickles, Entomologist 
of the Sugar Investigations Committee of Trinidad, and Mr. L. C. Scaranmzza of 
Cuba, left Georgetown for the Amazon district by way of the hinterland of 
British Guiana for the purpose of making collections of the parasite for shipment 
to this country. The first shipment of the parasite arrived in British Guiana on 
30th August, 1933. 

# Reprinted from Bullentin of Entomological Research , Vol. 30, Part 1, April 1939. 
t Seconded as Entomologist-in-charge, Sugar-cane Moth-borer Investigations, Colonial 
Development F^nd, July 1931 to April 1935. 



56 ac&icultoeal journal or &Rmsa guuna. tX 2. 

An account of the discovery of the fly, the return journey to Brazil and the 
collection and shipment of the insect from Brazil to British Ouiana, has been 
published already by Myers (11 ). 

The present account deals, therefore, only with such of the work as was 
undertaken in British Guiana either by the writer personally or directly under 
his control, namely, the receiving of the parasite in this country and the rearing 
of the flies from the initial shipments, the subsequent rearing of large numbers 
of flies for the colonization of the sugar-estates of the Colony, including the 
training of East Indian laboratory assistants for work on the sugar-estates and 
the supervision of the rearing work on the estates. This work extended over a 
period of twenty months, from September 1933 to April 1935. Since then, the 
writer has been closely associated with the Amazon fly situation in the Colony 
and during the past year (1937) was engaged on a status survey of the fly in 
British Guiana. In conjunction with Myers’ paper the present account should 
form a more or less complete record of the introduction and establishment of 
this insect in British Guiana. 

The introduction of the Amazon fly into British Guiana was the first im- 
portation of this insect into any country and its first use in biological control. 
Since then *the Amazon fly has been introduced into the Islands of St. Lucia, 
Trinidad and Puerto Rico from material bred m British Guiana, and into the 
island of Antigua from St. Lucia. These introductions do not come strictly 
within the scope of this paper so will merely be touched upon in another section. 

2. Introduction of the Parasite. 

Shipments received. —The collection and transport of the insect to British 
Guiana has been dealt with fully by Myers (11) and need not be repeated here. 

The first trial consignment of puparia was received in Georgetown by 
registered air mail (Pan-American Airways) on 30th August, 1933. Of the 57 
puparia sent on that occasion, flies had emerged from 31 en route and the insects 
were already dead when the package was received, and from the remaining 26 
puparia only three flies were secured and a fourth died during emergence. The 
air mail on this occasion was 23 hours late on its schedule in arriving at 
Georgetown, and this, no doubt, to some extent accounted for the high mortality 
of this consignment. The later consignments showed considerable improvement 
as regards the percentage of flies secured. 

From a total of 3,000 puparia shipped from Brazil, 1,409 flies, or 46.9 per 
cent, were secured in British Guiana ; 935 puparia (31.2 per cent.) failed to 
produce flies, while 592 flies (19.7 per cent.) emerged and died in transit, and 
64 puparia (2.1 per cent.) produced secondary parasites ; making a total of 1,591 
or 53.1 per cent, “failures.” 

Considering the long voyage, the difficulties of transport, and the narrow 
margin which the pupal period of the insect allowed to accomplish it, the 
number of flies secured must be considered good. 



Flfc. 2,— Sugar-cano Moth-borer Investigation Laboratory, 1M1 — 35, 
% at Sugar Experiment Station, British Guiana. 




THE AMAZON PLY (ItETAGONISTYLU M M 1 NENSE, TOWNS.) IN B&mstt GUIANA. 57 


Receiving and handling the material — The packages containing the puparia 
after coming down the Amazon in a special launch were posted by registered 
air mail at Para. The arrival of the launch at Para was made to synchronise 
with the departure of the Pan-American Airways plane which runs a regular 
weekly service between that port and Miami, Florida, U.S.A., via French, Dutch, 
and British Quiana and certain West Indian islands, and in this way a minimum 
of delay was obtained. 

The time of approximate arrival of the plane at Georgetown being previous- 
ly ascertained, the writer took charge of the packages personally at the General 
Post Office, Georgetown, as soon as the mail was recei\ed there, and conveyed 
them immediately to the laboratory. 

The puparia in the earlier shipments were packed in damp fibre, but later 
when bagasse* that was sent from British Guiana was available, in that material, 
in 2 oz. ointment tins, the number of puparia in each tin varying somewhat 
according to the total number in the shipment, the maximum being about fifty 
in any ono tin. The ointment tins were then packed in a liberal amount of 
cottonwool in a cardboard box and the whole wrapped. 

As the journey down the Amazon from Santarem to Para occupied some 
six days by launch, and the plane trip from Para to Georgetown a further day 
and a half, and as the puparia had to be collected some days before, it was natural 
that there should have been a fairly high percentage of adults emerging en 
route . The majority of such flies died before the receipt of the packages and 
constitute 37.2 per cent, of the total failures. Some of these flies, probably 
those which emerged only a few hours before the actual receipt of the 
packages at Georgetown, were always found crawling about in the tins when 
they were opened and it was possible to save a number of these. 

On arrival in the laboratory the packages were opened within a special 
glass-sided cage in order to secure any secondary parasites that might have 
emerged in transit, and the newly emerged flies which were found to be still 
alive were collected and transferred to suitable cages. The puparia were then 
sorted and those from which flies had emerged removed, the remainder being 
transferred, five at a time, to cylindrical glass lamp-chimneys of 2i inches 
diameter, one end standing in damp sand and the other being plugged with 
cotton-wool. In these the flies subsequently emerged and were transferred 
thence to cages. 

From the earlier consignments some of the flies were released within a day 
or two of emergence, and some retained for rearing trials in the laboratory. 

Secondary parasitism . — In spite of the care exercised at the sending end, 
as was to be expected, a small number of the puparia received produced 
secondary parasites. Of the 3,000 puparia received in shipments,. 64, or 2.1 


•Sugar-cane after the mice hid been extracted. With modern manufacturing methods it 
la reduoed to a fin# sawdust-like form. 



58 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


tX, 2. 


per cent., produced such secondary parasites. Three secondary parasites were 
thus secured, namely, Melittobia sp. (Eulophidae), Trichopria ( Ceratopria ) sp. 
(Diapriidae), and Signophora dipterophaga, Girault (Encyrtidae), the last of 
which, already known as a secondary parasite of Leskiopalpus ( Stomatodexia ) 
diadema, Wied., in British Guiana, being predominant. 

3. Bionomics. 

The fly Metagonistylum minense was first described by Townsend (19) in 
1927. Subsequently it was redescribed by Aldrich (1). In 1933 Monte (10) 
recorded it as attacking Diatraea saccharalis. 

The only country in which the insect is known to occur naturally at 
present is Brazil. In that country, however, its range is considerable. First 
recorded from the Lower Amazon district, it has been discovered recently by 
Harland (9) in the vicinity of Sao Paulo. Harland suggests that the insect 
in the Sao Paulo area is a distinct biological race. 

The adult of Metagonistylum minense is an insect of striking and char- 
acteristic appearance, and even in a general way ( is not likely to be mistaken 
for other flies parasitic on Diatraea, the large and prominent antennae, carried 

extended in front of the head, serving readily to distinguish it in the field. 

% 

The fly varies considerably in size, and may measure from 6.5 mm. to 
10.0 mm. long, and is about 3J to 4 times as long as it is broad. The antennae 
are black in colour, large and prominent, and protrude in front of the head; 
the front of the head is considerably produced and cone-shaped; the thorax 
is bluish-gray with two darker longitudinal stripes; the abdomen reddish- 
brown with a median darker stripe, showing bluish-gray reflections in certain 
lights, the last segment being much darker, and there are many strong 
bristles; the wings are large and strong and of a smoky brown colour, the 
legs are black. There is no difference in size between the sexes, but they 
may be usually distinguished superficially by the shape of the abdomen, the 
male abdomen being rather more blunt and more bristled than that of the 
female. 

The newly emerged larvae are small, measuring only 0.6 mm., and very 
active. When they become fully grown they may measure from 12.1 mm. to 
13.9 mm. in length. 

The puparium when first formed is chestnut-brown, but becomes darker 
later as development proceeds; it is oval in shape, both ends being evenly 
rounded, and may vary from 5.4 mm. to 8.8 mm. long and from 2.2 mm. to 
8.1 mm. broad depending upon the food available for the larva. It may be 
readily distinguished from the puparium of the other fly parasites of Diatraea 
by means of the anal spiracles. 

I . Life-history. — Myers (12) has given a short account of the life-history 
and bionomics of the fly, based partly on rearings on the Amazon and partly 
on the work in British Guiana. During the course of the very extensive 



tttE AMAZON PLY (MfifAGbMStYLUM M1NENSE, TOWNS.) IN BRITISH GUIANA. 59 


laboratory rearings which were carried out in British Guiana the writer was 
able to obtain considerable data on the life-history and bionomics of the insect 
and these will now be given. 

The total life-cycle of the insect varies from 10 to 27 days, of which 5 to 
9 days are spent as a larva within the host and 7 to 9 days in the puparium. 
Laboratory rearings of 20,556 individuals gave a mean life-cycle of 16.77 days. 

Of 20,666 flies, 6,132 (29.8 per cent.) had a total life-cycle of 16 days, in 
26.8 per cent, it was 17 days; in 15.0 per cent, it was 18 days; in 13.3 per 
cent, it was 15 days; and in 6.3 per cent, it was 19 days. So that for 91.2 
per cent, of the flies the life-cycle was between 15 and 19 days. The life-cycle 
varied from 10 days (0.39 per cent.=8 flies) to 27 days (0.001 per cent.=l 
fly.) 


The adult female deposits eggs which hatch immediately on deposition, 
the empty egg-shell being at times plainly visible to the naked eye, and two 
or three larvae are so released at a time. Deposition takes place either at 
the entrance of the Diatraea tunnel or on the cane-stalk in the vicinity of 
tunnels, and the young larvae may wander about considerably before finding 
a host, while doubtless a very large proportion never do encounter a Diatraea 
larva and consequently perish. One or more larvae may also enter a single host 
larva. 

When fully developed the larva leaves the host, which has by that time 
died and putrefaction set in, and pupation occurs either within the Diatiaca 
tunnel, behind a broad leaf-sheath of the cane, or the larva may fall to the 
ground where pupation takes place. From five to twelve days is spent in the 
puparium, after which the adult fly emerges. 

Mating . — Mating occurs from a couple hours after the emergence of the 
fly from the puparium to as long as six or more days after this. It takes 
place with the insects in the resting position, quite often with the head down- 
wards, but the body of the female is rather closely appressed to the surface 
on which she rests. The body of the male is generally in the same axis as 
that of the female, the forepart being raised somewhat on its forelegs and 
the abdomen depressed so as to make contact with the female. During coition 
the male sometimes makes violent convulsive and apparently excited move- 
ments as if to secure better connexion. The genitalia of the male are visible 
during coition. 

Mating commences at times with a short struggle, but at other times 
takes place quietly, the male merely approaching the female and getting into 
position. There appears, however, usually to be a preliminary “ love play ” in 
which the male strikes the female a number of blows with his abdomen, in a 
hammer-like manner and apparently with some force; meanwhile the genitalia 
of the male are extended visibly, the female offering no resistance and 
apparently accepting it as a normal proceeding. 



60 


AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


tX,2 

When the female is ready to accept the male she raises her abdomen and 
union is almost immediately effected. For a while after copulation commences 
the antennae of the male are held close against the front of the head but later 
are extended, sometimes first one and later both ; the antennae of the female are 
extended all the time. 

The time spent in copula is usually from ten to twenty minutes, but 
matings as short as two minutes and as long as seventy-seven minutes have 
been recorded, the average duration in 1,015 matings having been 15.98 minutes 
(Table I). 

Table I. 

Shorn tig Duration of Matings <>J Metagouistylum minense. 


Copuhtiou 11*3 i 19.4 


Minutes 

Sept 

! Oct 

Not 

| Dec, 

Jan 

Feb 

Mai 

A pi 

Maj 

1 June 


- 5 

-to 

1 

3 

i 

5 

29 

12 

16 

7 

r 

14 

6 

5 

3 

G 

90 

— ir> 

5 

1G 

46 

32 

3<) 

48 

57 

53 

53 

61 

412 

- 20 

3 

1 

G 

! 

19 

22 

Hi 

20 

44 

28 

40 

43 

270 

-25 

— 

1 3 | 3 

9 

n 

0 

14 

>(> 

26 

16 

129 

- 30 

1 

1 


.3 

5 

b 

3 

30 

1 1 

8 

50 

-35 

1 

1 

1 

5 

2 

3 

5 

1 

4 

1 2 

25 

-40 

— 


1 

1 

1 

— 

4 

3 

1 

2 

13 

-45 

— 

— 

— 

— 

- 

— 

2 

— 


1 

3 

- 50 

—55 

-GO 

- G5 

i - 

— 

— 


1 

— 

1 

1 

1 

1 

1 

4 

2 

2 

— i 


— 

— 

9 





1 

-70 

— | 

— 

— 

— 

— 

— 

— 

— 

1 

1 — 

1 

-75 

+ 

— | 

— 

— 



— 


1 — 

1 1 

' 1 


1 

1 

No. Pairs 

14 

28 

104 

84 

, 115 

102 

144 

139 

14G 

’ 139 

1,016 

Total minutes 

195 

421 

1,226 

1,2*8 

1 1,873 

1,541 

2,321 

2,491 

2 600 

2,252 

16,208 

emulation 
minutes— 
average ... 

13.9 

i 

15.0 

11.8 

i 

i 

15.3 

i 

36.3 

151 

16.2 

i 

17.9 

178 

16.2 

15.98 



THE AMAZON FLY (MBTAGONISTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 61 


It was observed early in the rearing work that a male would mate on more 
than one occasion, both with the same female and with different females. 
When mating occurred more than once with the same female there was either 
a complete separation of the flies with a loss of position of the male, or only a 
short interval in what could be mistaken for a continuous mating, the male 
remaining in position on the female during this time. Mating with different 
females on different days occurs also, and the data obtained in such instances 
showed that each female was fertilized, but there was a definite indication that 
the number of larvae produced gradually lessened. 

Females also have been observed to mate more than once, but in every such 
instance these matings occurred on the same day with short intervals only, and 
it would appear that such matings must be regarded as incomplete matings in 
the first instance rather than independent matings as in the males. 

The all-important factor in mating is the intensity of the light. In 
previous work on Tachinidae some stress has been laid on the size and type 
of cage used for the flies in order that mating may take place rapidly. When 
work with this insect was commenced, bearing this in mind, comparatively 
large cages were used, but it was soon found that mating occurred frequently 
in much smaller cages, and it became evident that some other factor was 
involved. Investigation suggested intensity of light, and further work which 
followed confirmed this. Later, when the correct intensity of light was ascer- 
tained, it was found possible to obtain matings at almost any time of the dav 
and in receptacles of any size, provided that the required intensity of light was 
obtainable, so much so that for laboratory purposes females were usually mated 
in 6 X 1 inch specimen tubes. 

When mating is about to take place, as soon as the required intensity of 
light is attained the flies become active, this activity being a peculiar restless 
movement which is characteristic. Should the light either increase or decrease 
in intensity this activity at once ceases. 

At first in order to standardise conditions the intensity of light was tested 
by means of a photographic exposure meter of the actinometer type, for want of a 
better instrument. The meter used was a simple comparator type, the Watkin’s 
Ilee Meter, which gave quite satisfactory results for general purposes. 

It has been possible since to carry out tests of the intensity of light at 
which mating occurs with a Sixtus photo-electric meter. From a series of such 
tests it has been found that mating occurs in lights of an intensity within the 
comparatively narrow limits, on this meter, of the upper portion of the 25 area 
(needle in line with figure 4 on lower scale) and the lower portion of the 50 
scale (needle at end of 4 area on lower scale) but usually about the upper end of 
the 25 area. In lights of intensities of either below or above the mating range 
the flies are usually quiet, thus at about the lowest quarter on the 25 area 



62 AGRICULTURAL JOURNAL OF BRITISH GUIANA. [X, 2. 

(25.1—25.2), as the lower extremity of the scale, and the highest quarter in the 
50 area (50.6—50.7), as the upper extremity, mating activity ceases. 



Fig. 1.— Sketch of Sixtus photo-electric exposure meter showing intensity of light 
(shaded area) at which matings of Meta</oni*tt/lu/n occur. The details of the meter with 
regard to emulsion speeds and f/valueg are not shown ns they have no bearing on the intensity 
of light with regard to matings of tho fly. 

Gestation , — About six (lays after fertilisation the female fly is capable of 
depositing eggs. It is presumed that under natuial conditions the fly would 
commence ovipositing as soon as this was possible and that each day such ova as 
were sufficiently developed would be deposited. For laboratory rearing it was 
found better to allow the female to go a couple of days longer before dissection 
in order to obtain a maximum of larvae for infestations. 

I Reproductive ca parti }/. — The reproductive capacity of the Amazon Fly is 
considerable. Dissections undertaken to determine this showed that a total of 
as many as 991 ova and larvae may be contained in a single female, and as few 
as 180 ov$ and larvae. The mean capacity of 100 females wae <559.1 ova and 



TOT AMAZON PLY (METAGONISTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 63 


larvae, and 188.7 ova and 368.7 larvae, with an average mating time of 17.8 
minutes. Table II gives the data in this connexion. 

The duration of mating does not appear to have any effect on the number 
of ova and larvae produced by a female. The longest mating in the 100 females 
was of 50 minutes duration and the contents of the uterus on dissection in this 
instance was 310 larvae and 257 ova (total 507), while the individual with the 
shortest mating, of only 7 minutes duration, contained 505 larvae and 235 ova 
(total 740) ; in both instances the dissection was made on the seventh day after 
mating. 

Table II. 

Showing Reproductive Capacity of Amazon Fly . 


Month 

No. of 
ilies 

Minutes 
mating — 
average 

Contents of uterus — average 
Larvae j Ova | Total 

1983 1 

December 

1G 

13.9 

322.1 

144.2 

466.3 

1934 






January 

31 

19.6 

421.3 

145.1 

566 4 

February 

2G 

15.7 

449.3 

184.4 

633.7 

March 

11 

14.7 

417.8 

191-5 

609.3 

April 

15 

1G.1 

2GG 9 

227.2 

494.1 

May 

1 

25.0 

345.0 

240.0 

585.0 

Total 

100 

107.0 

•> 999 1 

A., «■'«.* 

1,132.4 

3,354.8 

Mean 

___ 

17.8 

368.7 

188.7 

559.1 


Number of parasite* per host. — In the roaring of the parasite in the 
laboratory host larvae were infested with" one or two larvae according to the stage 
of development and size, with a preference on the whole for single infestations, 
especially when host larvae were obtained from an area in which the* fly was 
already established. That this method gave satisfactory results will be seen 
from the recovery figures of the laboratories given later. 

As to the number of parasites that will develop within a host under natural 
conditions, examinations have shown that with I), saccharafi * as the host from 
60 to b5 per cent, of the larvae parasitized contain but a single parasite larvae, 
from 25 to 30 per cent, contain two parasites, 6 to 7 per cent, contain three 
parasites, from 1.5 to 2.5 per cent, contain four parasites, and between 0.2 and 
0.3 per cent, contain five parasites. In one isolated instance in the .laboratory 
one host larva was found to contain 7 parasite larvae. 

Habits of adult. — The adult fly emerges under laboratory conditions 
invariably in tlSte morning hours between 8.30 and 11 o’clock, but emergence 



64 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[X, 2. 


occasionally occurs in the afternoon also, about 1 p.m. and even as late as 5.30 
p.m. The emergence of the fly appears to be dependent principally on 
temperature and humidity. 

In the cages the adult fly will rest on cane leaves or grass placed therein 
for this purpose or on the mosquito-net covering, and in so doing often assumes 
a position head downwards, which may probably be considered their more 
general resting position. 

In the field one does not often see the adult fly and then it is usually found 
resting on the underside of the cane leaves. The fly seeks this position for 
shelter from the sun during the heat of the day, and during rains also it has 
been observed to shelter thus. In the cooler periods during the morning and 
the evening they are to be found resting on the upper surfaces of the cane leaves 
and weed grasses in or near the fields. 

In the cages in the laboratory the adult fly feeds readily on sugar, which 
was found preferable to syrup in which they usually became entangled and died 
as the result. White sugar (refined sugar or washed muscovado) proved 
preferable to yellow crystals ; indeed, if fed on the latter, the mortality increased 
very considerably as well as the longevity being actually reduced. This high 
mortality with the use of yellow crystals was assumed to be due to the stannous 
chloride used in the process of making this grade of sugar, although it was never 
actually proved. Sugar of the dark crystal or muscovado grade (Java process) 
proved suitable for feeding also. Under field conditions feeding of the adult 
has not been observed. 

As to the longevity of the fly nothing is known under natural conditions 
In the laboratory flies have been kept for as long as 21 days, bub the majority 
survived from 10 to 12 days. Some flies died as early as the fifth or sixth day 
after emergence, which in females would be before the period of gestation 
would be completed, assuming that mating took place on the day of emergence. 

Host location . — In the location of the host there can be no doubt that the 
fly is guided by smell. Apart from the impossibility of seeing the host located, 
as it is within the cane, this has been amply proved in laboratory rearings. 

At the beginning of the work when little was known of the biology of the 
fly and the number of flies on hand was very few, it was not advisable, nor in 
fact would the material available allow of it, to dissect flies for rearing purposes 
and flies were induced to oviposit in order to obtain an approximate time when 
dissections might be undertaken. 

It was then found that flies with ovaries sufficiently developed would readily 
oviposit on a glass plate if a Diatraea larva was squashed and smeared on the plate ; 



fkE AMAZON il Y (METAGONlSfYtUM MINENSE, TOWNS.) IN BRITISH GUIANA*. 65 


in fact while they could be induced to deposit by this method they took little 
notice of a living Diatraea larva placed on the plate. 

This method proved further that there was no selection on the part of the 
adult as regards host, for they deposited just as readily in the presence of smears 
of Diatraea canclla larvae as in those of 1 ). saccharalis P That the larva of the 
parasite will not develop with equal facility in these hosts is another aspect that 
will be dealt with later. 


4. Species of Diatraea attacked. 

Up to the present, Mctagonistylum has not been recorded as attacking any 
genus other than Diatram and, according to Myers (11), it attacks two species, 
namely, D. saccharalis , which he states is the “ favourite host/’ and from which 
species the bulk of the material was obtained by him in the Amazon, and 
“another Diatraea apparently a new species allied to D. impersonatdla , the most 
destructive small borer in Trinidad.” 

Although it was known that Mctagonistylum attacked D. saccharalis at 
the time of its introduction into British Guiana, there was no information 
available as to whether the parasite would attack D . canclla , the other species 
commonly occurring in this country. 

The small amount of material in the early consignments did not allow any 
trials of this nature, and accordingly at the commencement of the work flies 
were released in fields regardless of which species of Diatraea predominated. 

As soon as it became possible, however, this point was investigated and a 
series of infestations of larvae ef both D . sacchwalis and D. canclla were 
carried out. The results of these infestations showed that, while a few larva of 
D . canclla may be infested artificially with the parasite, the large majority of 
fly larvae so used did not develop in this species. From a total of 6,523 
Diatraea larvae artificially infested, comprising 3,503 D. saccharalis and 
3,020 D . canclla , the parasite recovery was 36*0 and 1*2 per cent, respectively. 
From that time D. saccharalis was used exclusively for laboratory rearings of 
the fly. It should bo pointed out in this connexion that there is no actual 
difficulty in infesting D. canclla larvae artificially, but the parasite larvae 
invariably fail to develop beyond the second stage, apparently owing to some 
physiological condition of that host. 

The failure of some of the early releases of flies made in young ratoon 
fields in which there was a large preponderance of D . canclla and in which 
recovery of the* fly was not accomplished was also thus explained. Later, as the 



66 


AGRICULTURAL JOURNAL Of &Kim& GUiANA. 


t* 1 

work became better organised, when an area was being stocked with the 
parasite, counts were made to ascertain the density of the Diatraea population 
and the preponderant species. 

More recently as the result of inquiries of sugar planters as to whether the 
parasite would not eventually develop a strain that would attack 2). cauelta 
more successfully, and if this desirable condition could not be arrived at by 
laboratory rearing, work was undertaken in this direction. 

This work has already formed the subject of a paper by the writer (5), 
and it will be necessary to state here only that in rearings oxtending over a year 
and comprising three separate groups of material through ten generations with 
a total of 6,795 ZL cane/la larvae artificially infested, an average of less than 4 
per cent, produced puparia. There was no significant difference between either 
groups of larvae or generations and therefore no indication that the parasite 
could be reared in numbers on this host, nor of the development of u strain of 
the parasite more adapted to survival in this host species. 

f 

' 5. Colonisation of British Guiana. 

Hearing the fly in the laboratory . — In the rearing oi the fly in the labora- 
tory the method followed was that suggested by Thompson (18) and successfully 
employed by Scaramuzza (15) and Box (2) in the rearing of Lucophayu , with 
such modifications as appeared necessary for this particular insect. For 
convenience a detailed account of the technique and the apparatus used will be 
given. 

In the first instance gravid females which are known to have mated eight 
days previously are anaesthetised with carbon tetrachloride. As soon as the 
fly is dead, the uterus with its contained larvae is removed in physiological salt 
solution, the uterus being then ruptured and the larvae released in the salt 
solution. Daitraea larvae, previously collected from the fields, are then infested 
by placing upon them, by means of a small sable-hair brush, larvae ot 
Metagoni sty turn . The infested Diatraea larvae are then placed in 1 oz. ointment 
tins (salve tins) where they remain for some three hours and are then transferred 
to young cane-shoots. The cane-shoots with the contained moth-borer larvae 
are then stored in special tin-boxes for a period of twelve days. Puparia 
obtained from these tins are kept for the emergence of flies, or balloon fly-traps 
are attached to the tins and the flies emerging are thus secured. From these 
flies a number of known mated females are retained for laboratory use, and the 
remainder liberated in the fields after a period of from five to eight days, being 
kept during this time in the mating cages, where further matings Occur among 
tdb females not previously mated. 

A modification which was adopted generally in the work here in British 
Guiana -was to place Diatraea larvae directly into cane-shootsofter they were 



Ikfc AilAZON fLY (METAGONISTYtUM MINENSE, TOWNS.) IN BRITISH GUIANA. 6? 


infested with the parasite. This considerably shortened the work and the 
recovery of parasites from such larvae was equally as good as, if not in fact better 
than, with the tins. 

At first large circular cages 24 inches high and 18 inches in diameter were 
used for mating, but later, when it was discovered that the size of cage did not 
affect mating, smaller cages were adopted and cages 18 inches high and 14 
inches in diameter were used as standard. In these cages, under suitable 
conditions, mating takes place readily, and they serve also to store flies until 
they are liberated in the fields. These cages have four uprights and a single 
cross-bar at one end by which they are suspended, and were made of i-inch 
iron-rod welded at the joints. To each frame a bottom pan of galvanised iron 
with sides inches high is fitted and wired into position ; the whole is 
enamelled white. A cylindrical cover of mosquito net, made to fit tightly and 
in the sides of which are two sleeves, is drawn over the frame and is closed by 
means of tapes at the top and bottom. When flies are being kept in a cage, a 
circular piece of gunny-bag (sugar bag) is placed in the bottom and this is kept 
constantly damp. Two glass receptacles (Syracuse watch-glasses), one 
containing sugar and the other a piece of cotton wool saturated with water, are 
placed in each cage, while in addition a bowl of water in which is standing grass 
(Pasjtalum vepens) may be included. 

It has been found that infesting the Dint ram larvae with the parasite is 
best accomplished by means of a fine sable-hair brush, and good quality water- 
colour brushes of No. 1 size proved very suitable. Further, in doing this, if a 
number of larvae are removed from the salt solution at one time and placed on a 
black plate in a vertical line, it facilitates the work of infesting, as they may 
readily be seen as they walk out of line about the black plate. By this method 
assistants are usually able to work without the aid of even a low-power lens, but 
for less keen eyes a circular reading glass about 3 inches in diameter mounted 
in a flexible arm proved a very useful aid. 

Each Diatraoa larva is wetted with a dab of salt solution before the 
parasite larvae are placed on it, and what *was found to work even better was to 
keep the larvae ( D. scirrhamlis) in glass tumblers and to transfer lots of 10 larvae 
at a time to a potri dish containing salt solution prior to infestation, the larvae 
being taken from this dish and infested immediately. 

Should the Dial ram larvae be about full-grown, two parasite larvae are placed 
upon them (these are referred to as “ doubles”), while if they are about third instar 
or rather undersized, they are infested with only one parasite larvae (“ singles ”). 
Small larvae are not infested. 

If the tin method is used, a piece of blotting or filter paper wetted with salt 
solution placed in each tin greatly improves the chances of survival of parasite 
larvae Which tnjy drop or crawl from the host after it has been infested, and the 



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AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


t*. 1 

infestation is greatly improved by this means. A thin coating of paraffin wax 
applied to the inside of each tin retards corrosion and so prolongs the useful 
period of these receptacles. 

In the direct shoot method the infested larvae are placed in small cane- 
shoots in which a small pit has been cut previously, and as each larva is placed in 
the shoot and directly infested a small rubber band is placed round it to keep it 
closed. Subsequently shoots with infested larvae to a total of ten are slipped 
under one band, and they are placed in such bundles in the storage tins. 

The cages used for storing cane-shoots containing infested larvae are 
galvanised iron cylinders (known as the “ body ”) to which are fitted tops and 
bottoms, and are of two sizes, namely, 11 inches high by 10 inches diameter, and 
11 inches high by 7 inches diameter. In each body about half-way between the 
top and bottom edges is cut a circular hole of inches diameter around which 
is soldered a rim one inch high. The tops and bottoms are made to fit tightly 
inside the body so as to prevent the egress of Diatrara larvae, or when an 
outside cover is fitted a bead of about i inch projection is inscribed around the 
body about 1 £ inches from the top and bottom edg&s so that when the covers are 
in their places their edges come in contact with the bead, so making the body 
secure against the escape of the Dint rant larvae. To the circular opening in the 
body is fitted a cap of mosquito wire-mesh which affords ventilation to the 
cages and prevents excessive condensation of moisture within. 

In storing the cane-shoots in these tins a layer of damp bagasse or sawdust 
is placed in the bottom pan and the shoots with the contained larvae stood upon 
this. It is essential to the production of parasite puparia that the moisture in 
these tins should be regulated to prevent the drying out of the shoots or the 
development of excessive moisture, which causes the formation of moulds. The 
temperature in these tins is surprisingly low and constant when thus prepared 
and is in the vicinity of 29-30 J C. even when there is a good deal of beat being 
generated by the rotting cane-shoots; the relative humidity being in the vicinity ot 
100 per cent. The storage tins are each numbered on the body, top and bottom, 
from 1 to 31 and the shoots stored therein according to the date of the month on 
which the contained larvae wore infested, “doubles” and “singles” being kept 
separately for the purpose of working out the percentage of recovery. 

After the cane-shoots have been stored thus for 12 days, balloon fly-traps 
are fitted to the opening, the circular cap being first removed, and in a day or so 
the flies commence to emerge. The balloon fly-traps fitted to these tins were of 
local construction and measured 9 inches long by 2 \ inches in diameter with a 
cone about 3 inches high, the top being made in the form of a cap which was 
readily removeable to allow of the transference of the llies. 

k In practice, these balloon traps were often abandoned, however, and the 
puparia actually searched for by tearing apart the shoots. This was rendered 
somewhat easier than may be generally imagined by the decay of the shoots* 
and assistants with nimble fingers do not injure many puparia/’ 



THE AMAZON FLY (METAGONISTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 69 


The puparia obtained are then placed on damp bagasse or sawdust in 2 lb, 
jam bottles covered with wire-gauze tops. 

The method of storing in tins and securing the flies in traps, if it does not 
greatly increase the number of flies obtained, certainly effects a considerable 
saving in time, and on the whole is a marked improvement on tho former 
practice, but for estate practico tho searching method was generally preferred. 

Mated female flies kept for laboratory use are confined in 2 lb. jam bottles 
from which the central area of the cover has been cut and mosquito wire-gauze 
substituted. In each bottle is placed a piece of blotting paper on which there 
are a few crystals of sugar. One lb. jam bottles may also be used for this 
purpose and have proved entirely satisfactory. The sugar used must be either 
granulated white or dark crystal (muscovado). 

It was found convenient when working in small spaces, as were most of 
the insectaries used ip the work, to suspend tho mating cages from the top of 
the insectary, and to arrange a counterpoising weight run over a couple of pulleys 
to allow the easy lowering and raising of the cages. The mating cages in the 
present instance weighed approximately 10 lb. and as counterpoising weights 
sash window weights or small bags filled with sand were used. Double-decked 
tables are also a great saving in space. 

Temperature and humidity both play an important part in the artificial 
rearing of the insect (as will be observed from the statements made elsewhere 
in this piper) and must be regulated as tar as possible. The methods used in 
obtaining the desired temperatuies and humidities ha\e already been mentioned. 
It remains only to say that in the storage tins for shoots the temperature was 
much less than would be generally imagined with the decay of shoots taking 
place therein, and was generally found to be about 30^C. while the humidity 
was in most instances nearly 100 per cent. R.H. In the laboratory temperature 
and humidity readings are taken three times a day, namely 8 a.m., 1 p.m., and 
4 p.m., and there is also a self-recording thermo-hygrograpli. 

Laboratories . — A laboratory was erected for the investigation on the Sugar 
Experiment Station from a free grant made to tho Colony by the ^Empire 
Marketing Board for the purposes of sugar-cane research. A portion of equip- 
ment was also met from this grant. Later, with the actual introduction of the 
Amazon fly it was found necessary to enlarge the laboratory as well as to add to 
the equipment and apparatus, and this was met by funds provided by the 
British Guiana Sugar Producers’ Association. 

The laboratory as first erected was a small detached building 37 ft. long by 
17 ft. wide, of wood framing and concrete stucco panels, .raised on concrete pillars 
3 ft. high, a part of the building measuring 9 ft. by 17 ft. being screened with 
brass mosquito wire-mosh for use as an insectary. In order to protect the 
insectary against driving rains three small sloping glass roofs were affixed 
around the exterior. Later the building was enlarged by extending the 
insectary a further 10 ft, 



70 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. ’ 


tx,a. 

On the sugar estates there has been a great diversity of typo of insectaries, 
as might be expected, it being very often a matter of making an existing 
building serve the purpose ; thus we have worked in structures varying from 
what might be considered as ideal for a field laboratory with well-made benches 
and adequate apparatus, housed in a good building properly painted, to a 
structure that started its life as a large dog-kennel and immediately prior to the 
work was a calf-pen with a low, leaky roof and roughly put-togother benches of 
undressed wood. 

The size of the insectaries used throughout the work both at headquarters 
and on the estates approximates 324 sq. ft., being roughly 18 ft. by 18 ft. With 
three assistants working, some 200 to 300 flies per day were produced in such 
laboratories, the number being regulated largely by supplies of Diatraea larvae 
from the fields. 

Colonisation of the Sugar Estate *. — At the time of the arrival of tlio 
first consignment of the parasite nothing was known of its bionomics, and the 
small number of flies (3) obtained from this shipment did not allow of any 
knowledge being obtained in this respect. So that when the second consignment 
arrived it was still unknown whether the insect would be amenable to laboratory 
rearing. 

It was decided, therefore, to make liberations directly into fields of some 
of the adult flies emerging from the consignments pending the investigation 
of the bionomics of the insect and the matter of laboratory rearing. 
Accordingly, liberations of flies from the 3rd and 4th consignments were made 
in September and October. 

At that time the weather was hot and dry, as is usual at this period, and 
Diatraea was generally scarce, and of those present D. canella predominated. 
No recoveries from these liberations were recorded and, as mentioned elsewhere, 
it is believed now that this was largely due to the preponderance of D. canella 
in the fields in which the liberations were made. 

Liberations of this nature were made also with flies from the 5th and 6th 
consignments. During the first week in November (2nd and 9th) in a field 
of plant canes at Pin. Non Pareil (NP 29) 314 flies were liberated, and on 
22nd November two puparia were found in a single bored shoot from which, 
on the following day, two Amazon flies emerged. Thus about three months 
after the arrival of the first flies in British Guiana the first recovery of the 
parasite was made. 

In the meantime it was found that the technique which had been 
employed in connexion with the rearing of Lixophaga was also applicable to 
Metagonistylum and laboratory rearings had already been commenced. 
Diatraea had been infested in the laboratory as early as 21st September from 
fhes of the 2nd consignment, which arrived on 12th September and from which 
tne first flies emerged on the following day, and the first laboratory reared 
flies were obtained on 7th October, 1933, 



THE AMAZON FLY ( MET AGON ISTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 71 

From that date regular laboratory rearings continued. For the next 
eighteen months, and during the course of the work under the Colonial Devel- 
opment Fund grant, flies were reared and liberated on, or breeding stock 
supplied to, every sugar estate in the Colony. 

Liberations having been made under suitable conditions, it was usually 
but a few weeks before recovery of the parasite could be made. 

At the commencement the headquarters laboratory undertook the rearing 
of all flies and supplying of estates, the Diatraea larvae for use in the 
laboratory being sent in by different plantations. As time went on it became 
evident that if the entire sugar-growing area was to be stocked within a 
reasonably short period it would be necessary to produce much greater numbers 
of the fly than the facilities of the headquarters laboratory would allow. 
Accordingly, the co-operation of the sugar estate authorities was sought, and 
readily obtained, and arrangements were made to start rearing the insect in 
field laboratories on certain of the larger plantations. Assistants for work in 
these laboratories were obtained from the estates themselves with the aid of 
the managers and these were trained in the technique of rearing the insects at 
the headquarters laboratory. Ten such field laboratories were thus established 
on estates. These laboratories, with the exception of Pin. Albion were directly 
under the supervision of the writer; the laboratory at Pin. Albion was under 
Mr. H. W. B. Moore, entomologist of that estate. These laboratories were 
established at centres that were some distance away from headquarters and to 
which it would have been difficult to send continuous supplies, or where the 
area under the control of one group was large and it was more convenient to 
do this. For the nearer plantations as well as the smaller ones, headquarters 
laboratory supplied flies up to March 1935, when the grant terminated and the 
writer went on leave. 

Careful supervision was maintained over the work of these laboratories. 
A weekly report on the working of each laboratory was received and frequent 
visits were paid to them as appeared necessary. As to the efficiency of the 
work at these field laboratories it may be stated that it was generally 
satisfactory and in some instances it reached a very high standard, the recovery 
of puparia having reached as high as 96 per cent, larvae infested, while the 
recovery of flics reached 95 per cent, puparia. 

Up to the time of the termination of the grant (March 1935) that is, at 
the end of eighteen months, some 195,677 flies had been reared in all 
laboratories. Of this number, 25,226 or 12.8 per cent, were produced at the 
headquarters laboratory. 

Since that time some 180,020 more flies have been produced on the sugar 
estates, making a grand total of 379,697 flies produced in all laboratories over 
the period of two years since its introduction. 

The actual number of flies which were liberated was, however, considerably 
less than the figures given above. As regards headquarters laboratory, a total 
of 25,339 flies was reared during 1933-35 and 18,174 were distributed, that is, 
71.7 per cent. In addition, some 2,000 flies were used in tjxq laboratory, 



72 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


rx,2. 


6. Cost of Introducing the Parasite. 

It is difficult to state any exact figure of the cost of introducing the Amazon 
fly into British Guiana owing to the conditions and arrangements under which 
the work was carried out. Nevertheless, a figure, which for general purposes 
may be taken as representative of the cost of the introduction of the parasite, 
has been arrived at and in order to complete this record it is felt that it should 
be included here. 

As has been stated previously, the British Guiana Sugar Producers’ 
Association provided funds to the extent of £2,000 for the actual cost of the 
introduction. This amount provided for the purchase of a special launch for 
work on the Amazon and its transportation through British Guiana thence, the 
transportation of the personnel and supplies of the expedition, the pay of such 
members of the expedition as were specially engaged for the purpose, the 
expenses of collecting the parasite in Brazil and its shipment to the Colony, and 
the pay of the junior laboratory staff at Georgetown. 

Other charges which should be included properly in the cost of the 
introduction, but which were in fact not thus charged but were paid either 
from Imperial, Colonial, or other funds, would be the salaries of both Dr. Myers 
and the writer. 

Making allowances for such charges and also for some other incidental 
expenses, but not including previous ecological work done on Diatraea, the total 
cost of introducing the fly into British Guiana, as distinct from the colonisation 
of the estates, that is, for the work covering the period April to December 1933, 
did not exceed £5,000 ($24,000). 

From the material received in the Colony it has been shown that 1,400 
flies were secured, and basing the cost on this number only, the cost per fly was 
$17.10. In actual fact, by the end of December 1933, some 3,384 flies had been 
obtained (including 1,400 in original shipments) and of these, some 2,690 flies 
had been distributed to the sugar estates, and if the costs are worked on this 
latter figure of 2,690 flies, the cost per fly was only $8.92 or £1 17s. 2d. 


7. Parasitism of Diatraea saccharalis in Rice and other Host-plants. 

The Amazon Fly has been observed to parasitize Diatraea saccharalis in 
this Colony in other host-plants as well as sugar-cane. Only a few months after 
its introduction the fly was recorded as parasitizing D. saccharalis in the rice 
fields adjacent to the Sugar Experiment Station where the headquarters labora- 
tory was situated, and later it was recorded in this host-plant in other localities 
as well. 

Since that time there have been observed a number of instances of 
parasitism of D. saccharalis in rice. During the past year this parasitism 
appears to have increased, but no data are available to confirm this. 



THU AMAZON FLY (MJ3TAGONISTYLUM MINBNSE, TOWNS.) IN BRITISH GUIANA. 73 


That D. saccharalis in rice should be attacked is not surprising ; in fact, 
it was what was expected, for the aquatic nature of the crop offers conditions 
which it seems would be favourable to the development of the fly. The 
importance of this lies in the fact that rice, which is the second important crop 
of the Colony, is at times seriously attacked by D. saccharalis and at all times 
acts as an important alternative crop for the pest. 

On sugar estates either in cane-fields or rice-fields or in their immediate 
vicinity, the Amazon fly has been recorded also as attacking 1). mccliaralis in the 
grass hosts Kchinochloa polystachya (IJBK), Hitch., E , crasgalli cruspavoris 
(HBK), Hitch., “Bamboo Grass,” llymenachne amplcamivlia (Rudge), Ness., 
“ Bissy-bissy,” Cypcrus articulatus, L.,and Para Grass, Panicum harbinode , Prin. 

8. Status in 1937. 

Examinations made on sugar estates at different times after the introduc- 
tion of the Amazon fly into this country showed long since that the insect had 
established itself not only in sugar-cane but also in rice, and as regards the 
former crop at least was parasitizing a fair proportion of the Diatraca saccharalis 
in that host-plant. 

A survey carried out about the middle of 1935 by Mr. F. A. Squire, while 
engaged as Supernumerary Entomologist in this Department, showed further 
that some two years after the introduction of the parasite and the colonisation 
of the sugar estates the insect was still doing good work. The results of this 
survey were not published. 

About a year ago it was considered desirable to undertake another survey, 
and in January 1937, the work was commenced, continuing as opportunity 
allowed, to January 1938. In the survey it was not possible to carry out 
examinations of all the sugar estates in the Colony, but fifteen sugar estates were 
examined extending from Pin. Skeldon on the extreme east of the Colony to 
Pin. Versailles and Schoon Ord on the West Bank of the Demerara River. It is 
believed that the number of estates examined and the area over which they are 
extended are sufficient to allow the results to be considered as being representa- 
tive of the general conditions over the sugar-growing area. 

As regards Pin. Albion, Berbice, the survey of that estate was carried out in 
conjunction with Mr, H. W. B. Moore, entomologist of that estate, who undertook 
the field collections of material. 

A total of 212 fields was examined, comprising 88 plant fields, 54 first 
ratoons, 56 Second ratoons and 14 third ratoons. In 155 fields (73.1 per cent.) 
the Amazon fly was found parasitizing either /). aaccharalis or D . canella or both, 
144 fields showing a parasitism of D. saccharalis only, but no field was found in 
which only D. canella was parasitized. 

In these fields a total of 37,332 “ deadhearts ” were cut out, of which 20,998 
or 56,3 per cer^t. were empty. Of the remainder, 14,274 (37.9 per cent, of the 



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AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[X, 2. 


total) contained living Diatraea , in the proportion of 6,271 or 43.9 per cent. 
D. saccharalis (the black-headed borer) and 8,003 or 56.1 per cent D , canella 
(the yellow-headed borer) j 2,060 or 5.5 per cent, of the 14 deadhearts ” were the 
result of other causes, including white grubs (hard-back beetles) and rats. 

In 5,371 D. saccharalis found in positive fields, 863 (16.0 per cent.) were 
found to be parasitized by the Amazon fly at the time of examinations of the 
fields, the parasitism ranging from 3.4 per cent, to 36.2 per cent. While of the 
total of 212 fields, 39 (18.4 per cent.) showed parasitisms of 1). saccharalis of 30 
per cent, and over. If, however, all the fields examined are included, both 
positive and negative, the parasitism works out at 13.7 per cent. 1). saccharalis . 

The parasitism for 7). canella , as expected, was low, 0.32 per cent, for 
positive fields and 0.23 per cent, for all fields. 

Records were kept during the survey as to the number of parasites per 
host. Of a total of 863 Diatraea saccharalis records, it was found that 513 or 
59.4 per cent, contained only a single parasite, 263 (30.5 per cent.) contained 
two parasites, 66 (7.6 per cent.) contained three parasites, 17 (1.9 per cent.) four 
parasites, and only 4 (0.5 per cent.) contained five parasites per host. 

The puparia of the fly found in the field agreed very closely with these 
figures and wore in the proportions of 59.4, 31.4, 7.5, 1.4 and 0.3 per cent, for 
one, two, three, four and five parasites per host respectively. 

In January 1937, Mr. H. W. B. Moore recorded a hyperparasite of the 
Amazon Fly from Pin. Albion, Berbice. 

This appearance of a hyperparasite was not unexpected, for it had long been 
known that the native fly parasite of Diatraea > Leskio/talpax (Stomatodexia) 
diadema , Wied., was attacked by the hyperparasite Sign iphora dijderophaga , 
Girault, and the possibility of this insect attacking Metagonistghnn was well 
recognized at the time of the introduction of the Amazon fly. This was con- 
firmed when a determination of the insect was made by Dr. C. Ferriere of the 
Imperial Institute of Entomology. 

In addition, Squire (16), in his report of 1935, had mentioned tho finding 
of a puparium of Metagonistgluni which had apparently been attacked by a 
hyperparasite, although he did not obtain any specimens of tho insect. 

Accordingly, daring the survey, precautions were taken to secure hyper- 
parasites in order to obtain data as to the prevalence of the insect. 

On four estates of the fifteen the hyperparasite was obtained, namoly, Pins. 
Port Mourant, Albion, Diamond and Farm. This would indicate that the hyper- 
parasite is well distributed over the sugar area. 

% 

Of the 45 fields examined on these estates, in 13 (29 per cent.) hyperpara- 
sites were found, while of 178 puparia collected, 17 (9,6 per cent,) produce4 



THE AMAZON FLY (MBTAGONISTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 75 

hyperparasites. If, however, the whole Amazon fly population of these fields is 
considered, namely 516 larvae and puparia, the percentage destroyed by hyper- 
parasites would be only 3.3 per cent. 

Commenting on the larval parasitism, Myers (11) in his review of the 
Diatraea situation in British Guiana in 1031, stated that the combined parasitism 
of the eight important parasites was 6.9 per cent, of the borers in cane. The 
larval parasitism by the Amazon fly of 16.0 per cent. I). media rails, in the 
present survey must, therefore, be considered as very satisfactory. 

9. Shipments of the Parasite to the West Indies. 

While perhaps not strictly within the scope of this report, in order to make 
the account of the work in the Colony complete, opportunity is taken here to 
make mention of shipments of the Amazon fly which have been made from 
British Guiana since its establishment here. 

St. Lucia . — As the result of a request from the Sugar Planters of St. Lucia* 
B.W.I., to the Brittsh Guiana Sugar Producers’ Association, a shipment of 
puparia of the Amazon fly was made to that island in November, 1934. The 
shipment was made by tho writer direct to Mr. Harold E. Box, entomologist 
engaged under the Colonial Development Fund, who was at the time stationed 
in St. Lucia (3). 

Two hundred and twenty puparia of the fly were despatched by air mail 
from Georgetown on 27th November 1934, and anived at St. Lucia the following 
day. Mr. Box subsequently reported that the puparia were received in good 
condition. Bearings of the fly were undertaken and the establishment of the 
insect in St. Lucia has formed the subject of a report by Mr. Box. 

Puerto Rico . — In December 1935, Mr S. M. Dohanian, of the Puerto Rico 
Experiment Station of the United States Department of Agriculture came to the 
Colony to obtain material of the parasite for shipment to Puerto Rico. Mr. 
Dohanian remained in the Colony until February 1936, during w hich period 
some 6,000 adult Amazon flies were sent by him by air mail to Puerto Rico. 
Consequent on the failure of the fly to establish itself in Puerto Rico, Dr. K. A. 
Bartlett, also of the Puerto Rico Experiment Station, visited tho Colony in 
September 1937 and made further shipments of the fly to Puerto Rico. 

Trinida/L — At the request of the Director of Agriculture, Trinidad, and 
with the approval of the British Guiana Sugar Producers’ Association, shipments 
of the parasite totalling some 800 puparia were made to Trinidad in September 
and October 1936. These shipments were made by the writer and were received 
by Mr. A. H. Pickles, entomologist, Department of Agriculture, Trinidad. 

More reoently, a further small consignment of flies was sent to Trinidad by 
Dr, K. A, Bartlett while he was in the Colony, 



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AGRICULTURAL JOURNAL OF BRITISH GUIANA, 


[X, 2. 


10, Acknowledgments. 

Any account of the work with the Amazon fly in this Colony would not be 
complete without acknowledgment of the assistance which I received in one way 
or another during the period. 

Firstly, I would mention Dr. J. G. Myers, with whom I was associated both 
in this work and for some period before, during which tho purely ecological 
investigations on Diatraca were undertaken. 

To the sugar planters of the Colony also I would tender my thanks for their 
ready and active help which was largely responsible for the success which 
attended both the Dtal mm ecological work and the subsequent colonization of 
the sugar estates with the Amazon fly, and especially to Messrs. J. C. Gibson, 
G. E. Anderson, G. M. Eccles, W. H. Richards, D. Mowatt and R. B. Hunter. 

Finally, I have to thank my laboratory assistants at headquarters laboratory 
as well as those on the sugar estates who readily put in extra time in order to 
make the work a success. 

References. 1 

1. Aldrich, ,J. M. (1933). Two reared species of Tachinids from South 

America. — Proc. Biol. Soc. Wash, 3 5, pp. 170-173, 1 fig. 

2. Box, II. E. (1933.) Outline of work in Antigua and St. Kitts during the 

year 1932. — Report on the introduction and establishment of the Cuban 
parasite, Ltrophaga diatraea Townsend. Antigua, p. 40. 

3. . (1933;. Further observations on Sugar-Cane moth borers ( Diatraca 

spp.) in St. Lucia. Introduction of tho Cuban Parasite Lurophaga diatraea 
Townsend. Report upon a visit to St. Lucia, August- September 1933, 
with an Appendix on the recommended biological Control of the White 
Coffee-leaf Miner ( Leucoptera coffeella $ Guer.) in St. Lucia. — 10 pp. 
7 refs. Castries. 

4. Cleare, L. D. (1931). Sugar-Cane moth-borer investigations in British 

Guiana: the present position. — Agric. J. Brit. Guiana. 5, pp. 13-21. 

5. . (1937). Experimental rearings of the Amazon fly Metagonistglum) 

minrme Towns.) on the yellow-headed sugar-cane moth-borer {Diatraea 
canetla Hmpsn.), — Agric. J. Brit. Guiana, 8, pp. 190-194. 

6. . (1938.) Status of the Amazon fly in British Guiana, 1937. — Agric. J. 

Brit. Guiana, 9, pp. 12-24. 

7. Dohanian, S. M. (1937). Tho introduction of parasites of the sugar-cane 

borer into Puerto Rico. — J. Agric. Univ. Puerto Rico, 21, op. 237-241. 

8. ^Dohanian, S. M. (1937). The search in the American tropics for bene- 

ficial insects for introduction into Puerto Rico. — Agric. Notes P. Rico 
Exp. Sta, Mayaguez, P.R. no, 76, 7 pp. < 



fkE AMAZON PLY (MBTAGONKTYLUM MINENSE, TOWNS.) IN BRITISH GUIANA. 77 


9. Haul and, 8. G. (1937). A note on two larval parasites of the sugar-cane 
moth-borer, in Sao Paulo, Brasil. — Trop. Agric. 14, p. 280. 

10. Month, 0. (1933). Um novo parasita da broca da cana ( Dinlraea 

saccharalis F.) e consideragoes sobro esta broca. — Bol. Agric. Zootec. Yet., 
6, pp. 559-563, 3 figs. 

11. Myers, J. G. (1931). Preliminary report on an investigation into the 

biological control of West Indian insect pests. — E.M.B., 42 , 173 pp. 2 
maps. H.M.S.O. London. 

12. . (1931). The discovery and introduction of the Amazon fly — a new 

parasite of cane-borers (Diatraea spp.). — Trop. Agric., 11, pp. 191-195. 

13. — — . (1935). Second report on an investigation into the biological control 

of West Indian insect pests Bull. Ent. Res., 26, pp. 181-252. 1 map, 

1 1. . (1936). Biological control of sugar-cane pests in the British West 

Indies and British Guiana. — Proc. Iut. Soc. Sugar-Cane Techn. 5, 
Brisbane, 1935, pp. 381-385. 

15. Scaramttzza, L. C. (1930). Preliminary report on a study of the biology 

of Lixnjthaga dinlraea, Tns. — J. Ecod. Ent., 23, pp. 999-1004. 

16. . (1933). Observations on certain Dial rat a parasites of Brazil and 

British Guiana. — Proc. 7th Ann. Conf. Asoc. Tecnieos Azucareros de 
Cuba, pp. 60-64. 

17. SQUIRE, F. A. (1935). Progress roport on the present status of the Amazon 

fly in British Guiana. (Unpublished Rep., Col. Devpmt. Fund.) 

18. Thompson, W. R. (1930). The biological control of insect and plant pests. 

— E.M.B.. 29 , 124 pp. H.M.S.O., London. 

19. Townsend, C. H. T. (1927). Synopse dos gencros muscoideos de regiao, 

humida tropical da America, com generos e especies novas. — Rev. Mus. 
Paulista, 1 5, pp. 205-385, 4 pis. 



TESTING LARGE NUMBERS OF RICE VARIETIES BY 
THE QUASI-FACTORIAL METHOD. 

BY 

P. A. CHAN-CHOONG, B.sc., A I.O.T.A. 

Assistant Plant Breeder, Department of Agriculture. 


Introduction. 

The plant breeder usually has to handle large numbers of varieties and 
strains and his function consists largely in selecting promising, and discarding 
unpromising, material from that at his disposal. He must therefore have some 
means of testing which will enable him to assess the capabilities of such large 
numbers quickly and precisely. 

f 

Replicated variety trials, in the form of randomised blocks or Latin squares, 
offer an efficient means of comparing the few superior varieties which emerge 
from the bulk of the plant breeding material ; but the initial processes of sifting 
and discarding involve the testing of too large a number to be satisfactorily 
handled in this way. As Yates points out “a Latin square containing the whole 
of the varieties is impossible, being both too unwieldy and requiring too many 
replications, and even randomised blocks containing the whole of the varieties are 
unsatisfactory, for the blocks are likely to contain too many plots to eliminate 
fertility differences efficiently.” 

Yates however has recently developed a new technique for testing large 
numbers. He calls it the Pseudo-factorial (Quasi-factorial in a more recent 
publication) arrangement and the Incomplete Randomised Block method. 

At the Rice Experiment Station, British Guiana, it has been the custom to 
base the preliminary judgment of a variety on its average performance in progeny 
rows, over a number of seasons, as oompared with the progeny row yields of the 
standard varieties, each variety being planted in a progeny row plot consisting 
of 10 rows, each 1 foot apart, with 114 plants per row also spaced 1 foot apart. 
Progeny rows are admirable for acclimatising exotic, and purifying impure, varie- 
ties and they serve a very useful purpose os small observation plots, but their 
yield figures can give only a rough idea of varietal yielding power, since owing to 
lack of replication, no estimate of the error due to soil heterogeneity, etc., can be 
made. Some effort may be made to remove soil variability by using systemati- 
cally placed controls or checks, but Yates has demonstrated that this is not likely 
to prove more efficient than the quasi-factorial arrangement. The quaBi-factorial 
arrangement was tried here for the first time in 1938 and proved so useful that it 
was thought that a description of the experiment and results might be of interest 
to other workers in this field. 



tfflsfriNG OP BICE) VARIETIES BY THE) QUASI-FACTOBUL METlIOt). 79 


Method. 

With numbers above 100 and up to 200, the quasi-factorial method with two 
or three groups of sets seems to be the most useful, since the large number of 
replications required in the incomplete randomised block method is hardly possi- 
ble on account.of many reasons, economic chiefly. In view of the fact that in the 
method with two groups of sets, too great a discrepancy may occur between 
estimates of error variance for comparing varieties in the same and in different 
sots, it was thought advisable to use the method with three groups of sets. 

169 varieties were tested, of which 70 were old selections made before 1937, 
41 were new selections made in 1937, 27 were hybrids bred at the station, and 31 
were imported foreign varieties. 

With the varieties in each set (p) = 13, the total number of varieties tested 
was 169 ( — p ’). These are arranged in a square, the varieties being designated 
by numbers u v w> using the first figure u to represent the rows, the second v to 
represent columns, and the third figure w being written in along the diagonals. 
The following square is obtained 

Ill 1 2.13 1 3.12 1.11.4 1.12.3 1.13.2 

2 1 2 2 21 2 3.13 2.11.5 2.12.4 2.13.3 

3 1 3 3 22 3 31 3.11.6 3.12.5 3.13.4 


11.1.11 11.2.10 11.3.9 11.11.1 11.12.13 11.13.12 

12.1.12 12.2.11 12.3.10 12.11.2 12.12.1 12.13.13 

13.1.13 13.2.12 13.3.11 13.11.3 13.12.2 13.13.1 

Three groups X, Y, Z are then written out as follows : 

Group X : as above 

Group Y : obtained from Group X by writing in rows for columns, and 
colums for rows, thus : 

111 212 313 11.1.11 12.1.12 13 1.13 

1 2.13 2 2 1 3 2 2 11.2.10 12-2.11 13.2.12 

1 3.12 2 3.13 33 1 11.3.9 12.3.10 13.3.11 


1.11.4 2.11.5 3.11.6 

1.12.3 2.12.4 3.12.5 

1.13.2 2.13,3* 3.13.4 


11.11.1 12.11.2 13.11.3 

11,12.13 12.12.1 13.12.2 

11.13.12 12.13,13 13.13.1 



go AGRICULTURAL JOURNAL OF BRITISH GUIANA. L3* &• 

Group Z : obtained from Group X by writing in the diagonals along the 
rows, thus : 

111 221 331 11.11.1 12.12.1 13.13.1 

212 322 432 12.11.2 13.12.2 1.13.2 * 

313 423 533 . . 13.11.3 1.12.3 2.13 3 


11.1.11 12.2.11 13.3.11 

12.1.12 13.2.13 1 3.12 

13.1.13 1 2.13 2 3.13 


8.11.11 9.12.11 10.13.11 

9.1112 10.12.12 11.13.12 

10.11.13 11.12.13 12.13.13 


Statistical Calculations. 

Total number of sets = 3p = 39. 

Each group is replicated twice, so that < 


Replications of each group 

(n) - 2 


Complete replications 

(r) = 3n = 

6 

Total number of blocks 

(b) = Sup = 

78 

Total number of plots 

(N) — Sup* = 

1014 


Each plot consists of two rows of plants 1 foot apart, spaoed 1 foot apart 
within the rows. Each row contains 34 plants. The sets were not arranged at 
random within each group, but the varieties were randomised within each block. 
The groups were laid down at random on the field. All yields are given in 
ounces. There were three groups X t , Y,, Z t , each with its replication X», Y 3 , 
Z,. 

The first step in the computations is to set out the yields of the individual 
plots as in Table I, where the yields of the first replication of the first group (Xi) 
are shown with the marginal block totals. To save space only a few sets are 
shown. These yields are then summed for each group : this is shown also in 
Table I for the group X where the figures represent the totals of the yields in 
Xi and Xj, and the marginal totals Xu . . and X.v. are collected according to set. 
It is now easy to tabulate the variety totals Tuvw as shown ; this is done in two 
ways so as to give the marginal totals Tu . . , T.v. and T . . w which are required 
in the next step. 


The next step is to prepare a table of the quantities Cu.., C.v. and C..w. 
These are correction terms based on the yields of the other varieties in the same 
set and values are obtained for every set in each group, these values being given 


Tu. . - 3Xu.. , T.v. - 3Y.v. 


T. .w - 3Z..w 


. Application 


of these correction terms to the actual means of the variety totals will result in 


the corrected mean yields shown at the bottom of Table I. Qa. . and C.v. are 



Table I. 

Varieties after Randomisation and Corresponding Plot Yields in Groug A’ 


Testing op rice varieties by the quasi-factoRIal method. 81 


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AGRICULTURAL JOURNAL OP BRITISH GUIANA, 


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TESTING OP RICE VARIETIES BY THE QtTASI-PACTORIAJ, METHOD. 83 


in the corresponding row and column of the table, but C . . w has to be picked 
out from the value w for the variety. Thus, 


12.13= 


477.50 ■ 
' G 


1.630 - 2.742 + 2.744 = 77.955. 


For the analysis of variance the sums of squares are required for total, blocks 
and varieties. The first two are calculated in the usual way. The sum of 
squares of varietes is calculated according to the following scheme : 



2 (Tuvw »)/ 3n 


= 6,585,602.0729 

+ 

2 (3Xu . .— Tu 

. y/Cmp ) 


+ 

2 (3Y , 

.v.-T. 

v.) 2 / 6np 

= 18,380.4960 

+ 

2 (3Z . 

.w-T. 

,w) 2 /Gup J 


— 

(3X 

. . .— T . 

. yi l.Snp'J 

1 

— 

(3Y 

. ..-T. 

. .) 2 /l8np 2 

) = - 639.8521 

— 

(3Z 

...-T. 

. yiiSap^ 

1 

— 

2 (Xu 

. . 2 )/np 

) 


— 

2 (Y. 

v. J )/np 


= -6,451,900.7152 

— 

2 (Z . . 

w a )/np 

J 

(varieties) 

— 



s.s. 

= 151,441.9716 


In this scheme the sum of squares for (groups + sets + varieties + mean) 
is given by 

S(Tuvw-) + 2 (3 Xn . Tu . .)~ + X (3Y . v T . v .)-* + >: (3 Z . . w-T. . w) 2 
3n Gnp 

~ (3? - T. ..) 2 + (3Y.. . — T . . +_(3Z . . T . . .Y 

18np’ J 

and the sum of squares for (groups 4- sets + mean) is determined from 
2 (Xu . ,~ ) + 2(Y.v. J ) T 2 (%. .w 2 ). The difference gives the sum of squares 
np 

for varieties. 


The analysis of variance now reads as follows : 



S.S. 

^ D.F. 

Vaiiance 

i 

i log 

' Calc, 
value of Z 

Blooks 

93,713.9786 

77 

- 

! 

i 

1 



Varieties 

151,441.9716 

168 

901.4 103 

3.4020 

1.3620 

Error , 

i 56,935.8697 

768 

72.0519 

2.1400 


Total 

301,091.8199 

1013 



• 


The reqaired observed values of Z at the 5 per cent, and 1 per cent, points 
do not exceed ,2654 and .3746, indicating that varietal differences are significant. 



AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


&4 


tX 2. 


Iu making comparisons the varieties may be classified according to whether 
they occur or do not occur in the same set, />., differing in two sets or three sets. 

If s® is the error variance, the variance of the difference between the means 
of varieties occuring in the same set is 

V (tuvw — tuy/wO — 2i ?'•* /I + _1_\ — 25.8(5 

3n V P/ 

S.E. = •/ 25.8(5 = 5.085 
and for varieties not occuring in the same set, 

V (tuvw — Wy/yy/) = 2s 8 /I + _3_\ = 2(5.78 

v 2 P ; 

S.E. =^2(5.78 =5.175 
The average variance of all comparisons is 

Ym = 2s 1 / p + 3i \ = 2(5.59 S.E. = v^cT.W = 5.15(5 
3n VP + 1 / 

Results. 

The differences between the error variances are not great, and for general 
purposes of comparison the average variance may be used. Twice its standard 
error may be taken as a significant difference. Table II gives the list of the 169 
varieties with their corrected mean yields arranged in order of descending 
magnitude and in groups of equality based on the significant difference of 
10.312 ounces. Thus D 162 is significantly inferior to the varieties in group (1), 
and significantly superior to the remaining varieties except those in its own 
group (2). The significant difference represents 13.1 per cent, of the general 
mean yield. 

There were two Demerara Creole selections, of which the better gave a yield 
of 81,153 ounces. Taking this as a standard of comparison, 83 varieties gave 
higher yields, of which 21 are significantly superior and 85 varieties gave lower 
yields, of which 27 are significantly inferior. 

Greater interest centres in the 21 superior varieties. These comprise 13 local 
selections (9 prior to, and 4 made in, 1937), 4 imported varieties and 4 hybrids. 
Except for the 4 selections made in 1937, these varieties had been under progeny 
row test for three to six seasons, and had, with the exception of one, given 
superior average yields to Demerara Creole. 

Of the 27 inferior varieties, 24 had given inferior average yields to Demerara 
Creole over three or more seasons, the other three had given yields about equal 
to this standard. With regard to the remaining varieties there has been the 
same general trend to follow the results of progeny row test over the last three 
or more seasons. 

It would appear that one replicated experiment along the lines of the quasi* 
factorial arrangement has served to confirm the results of three or more seasons 
ofLproffeny row testing. But further, this experiment has shown where varietal 
differences become significant and has pointed towards a few select varieties out 
of the great bulk, the behaviour of which can be followed up in additional 
testing. 



TESTING OF RICE VARIETIES BY THE QUASI-FACTORIAL METHOD. 85 


Table II. 


Corrected Mean Yields in ounces per plot of Varieties in Groups based on 

Significant Difference. 


(/) 108.830 — 98.524 


D99 (1) 

108.836 

71—37 

105.870 

D250 

101.190 

D99 (2) 

100.086 

(2) 98.310—88.004 

D162 

98.316 

Karimganj (1) ... 

07.781 

1)256 

07.350 

D257 

96.863 

Minalabon 

96.822 

Karimganj (2)... 

06.568 

3—37 

05.050 

1)222 

94.76 L 

D254 

04.736 

54—37 

01479 

23—37 

94.387 

15—37 

04.084 

1)238 

03.514 

20—37 

93.213 

D103 

02.078 

50—37 

01.000 

52—37 

01.406 

38—37 

01.112 

1)255 

00.023 

39—37 

00.887 

SN3 

00.864 

18—37 

00.427 

A K Kulu 

00.370 

A 16.34 

80.700 ■ 

70—37 

80.615 

16—37 

89.455 

56—37 

89.308 

D253 

89.354 

67—37 

89.050 

D258 

88.962 

5)1—37 

88.721 

55—37 

88.483 

D114 

88.324 

McK. Large (1) 

88.227 

42—37 

88.009 

( 3 ) 87.754—77.442 

Kalyaman (1) ... 

87.754 

63—37 

87.644 

19-37 

87,327 


D110(l) 

1)183 

r>i — 37 

14—37 

D80 

17—37 

57—37 

DUO (2) 

43—37 

SN7 

Kalyaman (2) 
D11G (2) 

SN8 
28—37 
37—37 
21—37 
D07 15 
McK. Small 
SN 5 
D247 

40— 37 
1)07 A 
30 -37 
0 14.31 
D02 

41— 37 
G5 — 37 
Lead Rice 
D205 

McK. Large (2 
No. 70 (1) 
08—37 
Ramcajara (1 
D100 (l) 

DUG (1) 

D88 
D250 
G9 — 37 
58—37 
8-37 
D221 (2) 

D297 
D.C. (2) 

D244 

34—37 

13-37 


87.147 
86.971 
86.787 
86.733 
86.495 
86.153 
86.078 
86.069 
86.038 
85.062 
85.550 
85.492 
85.439 
85.196 
85.145 
85.122 
84.822 
84.686 
84.566 
84.326 
84.326 
84.167 
84.000 
83.031 
83.869 
83.633 
83.348 
83.052 
83.048 
82.577 
82.272 
82.047 
- 81.896 
81.873 
81.830 
81.753 
81.660 
81.584 
81.381 
81.344 
81.266 
81.257 
81.153 
81.141 
81.050 
80.759 



86 AGRICULTURAL JOURNAL OP BRITISH GUIANA, [X, 2 

Table II.— {Continued.) 

Corrected Mean Yields in ounces per plot of Varieties in Groups bases on 


Significant 


No. 79 (2) 



80.662 

Ramcajara (2) 



80.587 

D108 



79.702 

D91 (2) 



79.341 

D94 



79.166 

61—37 



79.142 

66—37 



79.006 

D224 



78.817 

No. 76 (2) 



78.763 

32—37 



78.461 

Bamboo Rice 



78.165 

D135 



78.059 

B.S. (1) 



77.955 

26—37 



77.774 

44—37 



77.766 

D100 



77.582 

12-37 



77.471 

{4) 

77.347- 

-67.035 


D243 



77.347 

60—37 



76.622 

59—37 



76.596 

29—37 



76.353 

62—37 



76.159 

N. Patna 



76.040 

1)90 



75.998 

35—37 



75.887 

D246 



75.816 

SN 4 



75.521 

H7 



75.354 

1)225 (1) 



75.302 

47—37 



75.073 

64—37 



74.385 

S 



74.281 

D91(l) 



74.154 

D.C. (1) 



73.977 

D245 



73.962 

45—37 



73.946 

D242 



73.862 

31—37 



73.612 

Bommadeva 



73.599 

9—37 (2) 



73.173 

D%60 



73.160 


Difference. 

D225 (2) 



73.114 

No. 75(1) 



73.050 

25-37 



72.909 

Unity 



72.716 

SN2 



71.964 

P. Berbice 

* 


71.923 

5—37 (2) 



71.773 

D221 (1) 



71.349 

33—37 



71.312 

46—37 



71.121 

D156 



71.046 

D188 



70.886 

D109 (2) 



70.476 

36-37 



70.361 

49—37 , 



70.261 

B.S. (2) 



70.205 

D239 



69.841 

24—37 



(59.793 

No. 75 (2) 



69.7(59 

48—37 



68.816 

27—37 



68.303 

(-5) 

D184 

66 906- 

— o 5.5 9 3 

65.905 

9-37 (1) 



64.793 

SN 1 



64.232 

1)251 



(53.785 

4—37 (2) 


t • • 

63.765 

D228 


• M 

63.443 

No. 76(1) 


• t • 

63.302 

4—37 (1) 



61 685 

D 95 (1) 



60.488 

D266 


• • • 

60.063 

5-37(1) 


• • • 

59.337 

(«) 

D236 

58 947 and below . 

58.947 

Kao Bang Pra ... 


48.925 

D150 

• • • 


48.253 

D261 

• • • 


43.027 

D264 

• • • 


40.554 

D263 



37.144 

D262 

• • m 


36.834 

D267 

aM 


5.767 



TESTING OF RICE VARIETIES BY TIIE QUASI-FACTORIAL METHOD. 87 


Discussion. 

Ia all experimental work, whenever a new method is to be tried out, the 
question is certain to be asked — “ Is the new method more efficient ?”, and 
furthermore, if additional labour and computation are required, “Is the gain 
in efficiency large enough to compensate ?” In the introduction it was stated 
that the method used to gauge the yielding power of varieties was by use of 
progeny rows, where no significant differences in yields can be estimated. The 
quasi-factorial method is designed to measure varietal differences statistically 
and because of this may be considered more ellicient, although there is no gain- 
saying the value of progeny rows as observation plots. 

However, the planting of 2-row plots in four or six groups as opposed to the 
progeny row planting of a single 10-row plot will usually involve more labour in 
planting and reaping. The last crop (quasi-factorial method) and the one before 
(progeny row planting) were approximately of the tame magnitude, eo that costs 
may be reasonably compared. Expenses for planting and reaping showed an 
increase of roughly about $11 per acre. There is also extra labour involved in 
the statistical calculations but not enough to offer any serious obstacle. 

In considering the merits of the two systems, both the financial and time 
factors must be considered. The former system of progen > row planting meant 
that varieties had to be kept under observation for three or more seasons before 
some idea of thoir capabilities could be obtained. Even then, because of the 
absence of a satisfactory lay-out, the judgment was not sufficiently precise and a 
largo number of varieties had, for safety, to be included in the replicated variety 
trials. On the other hand, one or two quasi-factorial trials will suffice for the 
selection of the really good varieties. This saving in time will more than offset 
the extra cost of the quasi-factorial trials and, in addition there will be a saving 
in the variety trials proper since fewer varieties will reach this stage. 

The general conclusion may be reached that while progeny rows are very 
useful for acclimatising exotic, and purifying impure, varieties, the quasi-factorial 
method offers a more rapid and reliable means of testing a large number of 
varieties, and serves as a valuable preliminary to the full variety trials with their 
few select varieties. 

Summary and Conclusions. 

1. Attention is drawn to Yates’ quasi-factorial layout as filling the need of 
the rice breeder for a method which will facilitate the early discards and selections 
among a large number of strains. 

2. An experiment where the method was used for testing 169 varieties is 
described, and it is shown that differences of 13 per cent, in yield can be meas- 
ured, It is further shown that the results of the experiment are in good agree- 
ment with the average data from three seasons’ tests in progeny rows, 

3. The merits of the quasi-factorial layout, in comparison with accumulating 
data from progeny row plots are discussed and it is pointed out that although the 
former involv& 14 per cent, increase in field costs and more statistical com put a- 



88 


AGRICULTURAL JOURNAL OF BRITISH GUIANA. 


[X, 2. 

tion, it proves cheaper in the long rnn since a variety can be judged more quickly 
and it is possible to reduce, to a minimum, the number of varieties to be dealt 
with in the replicated variety trials. 

Acknowledgments. 

Thanks are due to Mr, C. H. B. Williams, Sugar Agronomist and Plant 
Breeder, for his suggestions regarding this experiment and the presentation of 
its results, and to F. 0. Ramotar of the Rice Experiment Station for his assistance 
in the conduct of the experiment. 

References. 

1. Yates, F. A new method of arranging variety trials involving a large 

number of varieties. Jour. Agrio. Science, 2G : 424455. 193G. 

2. The design and analysis of factorial experiments. Imperial 

Bureau of Soil Science, Technical Communication No. 35. 

3. Goulden, C. II. Modern methods for testing a , large number of varieties. 

Dominion of Canada Dept, of Agriculture, Publication 575, 
, Technical Bull. 9. 1937. 



DOUBLE VERSUS SINGLE PLANTING OF SUGAR CANE. 

BY 

C. HOLMAN B. WILLIAMS, M A., A I C T.A . Dip Agr., 

Sugar Agronowist and Plant Breeder , 

\xr> 

L. A. FORTE, 

Field Assistant , Sugar Experimeni Station . 

The opinions of British Guiana planters vary considerably as to the 
amount of planting: material to be used in a row and its ideal disposition (single 
line, staggered, double line, etc.), and the feeling is strongly held by some 
that single planting produces less but bigger stalks whose size more than 
counter-balances the weight of the larger number of thinner stalks obtained 
from double planting. The thicker stalks, it is often claimed, are a better 
commercial proposition, being cheaper to cut and load. 

To throw some light on the problem an experiment was started at the 
Sugar Experiment Station (Sophia) and the present paper gives the results 
secured from the plant canes and first ratoons. It is thus an extension of the 
report on the plant cane results made to the Sixth Congress of the Inter- 
national Society of Sugar Cane Technologists. 

The Experiment. 

Twenty-one pairs of plots were planted to P.O.J.2878, seven pairs in each 
of three different fields. It was felt that by spreading the test over three 
fields, planted and harvested on different dates, more confidence could be placed 
in the general applicability of any conclusions drawn. Each plot consisted of 
six rows and comprised an area of 0.02548 acre. One plot of each pair was 
planted double-row with twice the number of cuttings used to plant its mate 
single-row. In the single planting 36 cuttings were used to a row. The aver- 
age weight of a cutting was 0.48 lb., its average length 15.3 inches. At these 
rates it may be assumed that single planting would involve just under two and 
double planting a little under four tons of material per acre, the excess required 
by double planting under the conditions of this test being 1.82 tons per acre. 
The plots of each pair were contiguous along the same bed but the order of the 
two plots in each pair was determined by chance. The significance of the 
differences obtained was tested by Fisher’s modification of Student's method 
for comparing pairs of observations. 

The' numbers of the fields and the dates on which they were planted and 
harvested are listed below : — 

Field . Planted . Harvested. Age at Har - Harvested. Age at Har- 
vest , Months . vest, Months . 

15 East 19.12.36 3.3.38 14.50 27.4.39 13.75 

13 East 23. 1.37 26.2.38 13.00 28.2.39 12.00 

13 West £5. 2.37 9.3.38 12.50 26.4.39 13.50 



90 


AGRICULTURAL JOOIttAL OF BRITISH GUIANA. 


tX,2. 


Rains were abnormally high during the wet seasons and unusually low 
during the dry seasons in which these canes were growing as plants (see 
Table I) and the unusual weather conditions appear to have depressed the yields. 
The first ratoon yields were also adversely affected by six months of contin* 
uous heavy rains following the harvest of the plant canes. 

Table I. 


Rainfall at Sophia Sugar Experiment Station. 


Month. 

Rainfall, 

1936—39, 

Inches. 

Average Rainfall, 
1921 — 38, 
Inches. 

Excess or 
Deficit during 
Growth of the 
Experiments. 

December 193G 

23.04 

14.17 

8.87 

January 1937 

14 03 

9.18 

5.45 

February 

0.75 

4.27 

- 3.52 

March 

1.53 

4.78 

- 3.25 

April 

5.19 

5,4(5 

- 0.27 

May 

13.09 

11.77 

1.32 

June 

19.95 

14.37 

5.58 

July 

19.70 

11.26 

8.44 

August 

8.23 

8.54 

- 0.31 

September 

2.(51 

2.(58 

- 0.07 

October 

4.57 

3 95 

0.62 

November ... 

3.(50 

5.(53 

- 2.03 

December 

12.7(5 

, 14.17 

- 1.41 

January 1938 

13.72 

9.18 

454 

February 

14.20 

4.27 

9.93 

March 

14.7(5 

4.78 

9.98 

April 

8.94 

5.46 

3.48 

May 

11.14 

| 11.77 

- 0.63 

June 

12.99 

14.37 | 

-1.38 

July 

12.86 

| 11.26 

1.60 

August 

15.92 

, 8.54 

7.38 

September 

2.42 

1 2.68 

- 0.26 

October ... .... 

3.37 

3.95 

1 - 0.58 

November . . 

5.29 

| 5.(53 

1 - 0.34 

December ... 

7.71 

! 14.17 

- 6.46 

January 1939 

12.25 

918 

3.07 

February 

4.11 

4.27 

-0.16 

March 

4.78 

4.78 

— 

April ... ... 

; 

8.74 

5.46 

3.28 


The topsoils of these fields are acid silts overlying alkaline silt subsoils. 
The topsoils are rather low in organic matter while in the subsoils the carbon: 
nitrogen ratios of the organic matter are wide. 


For the plant canes, five weeks after planting, a plot by plot check was 
made o£ the number of shoots (denoted arbitrarily first ordlr shoots) and 



DOUBLE VERSUS SINGLE PLANTING OF SUGAR CANE. 


91 


each was labelled with a metal tag. Five weeks later another check was made 
and all new shoots (denoted arbitrarily second order shoots) were labelled with 
a differently shaped tag. At harvest only millable stalks were considered and 
it was determined how many out of the total for each plot were 4 first order 
how many 4 second order and how many were 4 late shoots as all shoots 
developing after ten weeks were arbitrarily called. 

Each group of stalks in each plot was weighed separately and, since the 
number of stalks present was known, it was possible to calculate the average 
weight per stalk. Further, from each group of stalks in each plot, fourteen 
average canes were measured and sent in as a sample to be passed through a 
power-driven experimental mill for purposes of analysis. 

For the first ratoons, only the weight of cane and number of stalks were 
determined, and a sample from each plot crushed for analysis. Consequently 
none of the data recorded in Table III is available for the first ratoons. 

Results and Discussion. 

Stalk PopvVation. 

Table II shows, for single and double planting separately, the number of 
first and second order shoots at the start of the experiment and the number of 
these present as millable stalks at harvest; also the number of late shoots 
present at harvest. The differences in favour of double planting are also 
recorded and marked with an asterisk when statistically significant. 

At all stages, in the plants, the double planting gave a greater number of 
stalks than the single. There was a considerable mortality among the early 
shoots and, as shown more clearly in Table III, it was heavier in the double 
planting than in the single but not sufficiently so to offset the much higher 
population of the double-planted area. It may be said that the higher mortal- 
ity used up just less than half of the initial advantage of the double-planted - 
plots. 

In the first ratoons the comparison was made only on millable stalks at 
harvest. Here again the double planting proved superior. 



92 


AGRICULTURAL JOURNAL OF BRITISH GUIANA, 


[X,2. 


Table II. 

Comparison oftho Number qf Stalks per Acre Produced from Single and Double 

Plantings. 



Young Shoots 

Mill a blr Cane at Reaping 


First order 
(alter 5 weeks) 

Reoond order 
(after 10 week*) 

First order 

Second order 

Late 

Total 


Singlt i 
PUnt- 1 
ing j 

Doublf 

1 Plant 
| mg 

1 

1 SmgU 
Plant 
mg 

Double 

Plant- 

ing 

Single 

Plant 

ing 

Double! 
Plant 
ID(t | 

Single 

Plant 

ing 

Doublt 

Plant 

ing 

Single 
Plant 
mg { 

Double 

Plant 

ing 

Single 

Plant 

mg 

Double 

1 llant 
mg 

No ( f Shoot* 

Plants 
l^t Ha toons 

7.417 

1 

1 

14,710 

11,178 

17, '90 

2.888 

i 

1 

4,717 

1 

i 

1.787 

4,70-1 

17,717 

16,543 

22 020 | 
21,877 

27 840 
24,278 

Difference m 
f a\ our oi Double 
Planting 

Plants • 

1st H itoons 










i 

1 


7 bn* 

f 412* 

1 647* 

1177* 

908* 

3 820* 

2 401* 

% Increase of 

Double on Single 
Planting I 

Plants 

1st Ratoons 

%04 

r >7 

61 

I 

56 06 

12 81 

i 

C 12 

I 

nr, 

1097 


•Difference Significant. 


Table III shows what percentage of first and second order plant cane shoots 
lived through to harvest and the numerical composition of the crop in terms of 
various orders. 


Table III. 

Fate of First and Seiond Order Shoots and Numerical Composition of crop by 

Shoots of Di fferent O* ders. 


Treatment. 

I 

% First Order Shoots 
| present at 

% Second Order Shoots 
present at 

% Composition of 
Harvest. 

' 

:> weeks. 

Harvest 

. 

1 

10 weeks. ^ Harvest. 

| First 
order 

1 shoots. 

Second 

order 

shoots. 

© 3 

31 

09 

Single Planting 
Doable „ 

100.00 

100.00 

38 93 
31.18 

100.00 32.14 

100.00 ! 27.08 

1311 

17.54 

16.29 

18.44 

70 60 
64.02 


* It will be seen that about two-thirds of the first order and a like portion 
oi the second order shoots disappeared before the cane was harvested and that 
mortality was higher when planting was double than when it was single. The 
differences in this respect are statistically significant. On the ether hand, the 



fcObfeLE VERSUS SINGLE PLANTING OF SUGAR CAN& 9)} 


ftrst and second order shoots formed 36 per cent, of the final crop in the case 
of the double planting against under 30 per cent, for the single planting. 

The population appears to have been about normal for P.O.J. 2878 in this 
Colony, comparing favourably with other counts made at various times and 
places. This is brought out in Table IV below, where counts for the two other 
standard canes are included for comparison. 


Table IV. 

Number oj Stalks per Acre at or near Harvest in British Ouiana . 


Variety. 


This 

Investi- 

gation. 


P.O.J. 2878 

Plants 23,930 

1st Ratoons 23,077 

Diamond 10 
D. 625 


vemr, 

1937. 


15,304 


, 1 

Rose Hail, 

1 1937. 

i 

i 

Port 

Mourant, 

1937. 

o .. (1) 

Sophia, 
(Cooper, . 
1937). 1 

i 

(2; 

Various 

Sites 

(Clearo, 

1938), 

(3) 

Rose Hall, 
( Falconer, 
1938), 

23,716 

26,264 

i 

i 

*20,1577 


i 

23,800 


1 !!! 

17,271 ! 
10,K23 | 

17,552 

13,785 



(1) Agric. Jnl , of British Guiana , VIII, No. 1, pp. 4 — 40. 

(2) „ „ „ „ „ VIII, „ 2, ,,63-83, 

(3) Private Communication. 

Weight Composition of Crop . 

The weight composition of the crop, in terms of various types of stalks, is 
shown in Table V. 

Table V. 


Percentage Composition of Crop by Weight in Relation to Shoots of Different 

Orders . 


First Order Second Order Late Shoots Total 


Single Double Single Double Single Double 
Planting. Planting. Planting. Planting Plant ; ng. Planting. 


Single | Double 
Planting. , Planting. 


I 


Weight of Cane 
per Aero, Tons. 
Plants 

1st Ratoons. 

' 2.63 

i 

4,15 

3 6G , 

4.78 

17.20 

> 17.61 

i 

23.49 

17.33 

26.54 

19.41 

% of Total, Plants : 

' 11.20 

15.64 

15 UK 

18.0! 

* 73.22 

60.35 

100.00 

100,00 


Double planting gave a total tonnage of cane 12.98 per cent, higher than 
single planting in the plants, and 12.00 per cent* higher in the first ratoons; 
in both instances the increment was statistically significant. In the plants, as 



94 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [X, 2. 

might have been expected, the increment was secured mainly in the first five 
weeks of growth and, to a lesser extent, in the second five weeks. The highev 
mortality in the double-planted plots was not sufficient to offset the markedi 
superiority of these plots in number of stalks per acre. The tonnage of late 
stalks was practically identical for the two types of planting, although, in thi» 
category, the double planting averaged 998 stalks per acre more (see Table II) 
than the single. 

In Table VI certain other effects of the two types of planting are com- 
pared. 

Table VI. 

Comparison of the Effects of Single and Double Planting on the Purity , Sucrose 
in Cane %, Glucose Ratio and Length and Weight per Stalk. 



First Order Shoots 

Second Order Shoots 

Late Shoots 


Single 

Double 

Differ- 

Single 

Double 

Differ- 

Single 

Double 

Differ- 


Planting 

Planting 

ence 

Planting Planting 

ence 

Planting 

Planting 

ence 

Purity 

Plants : 

85. G 

86.3 

-i 

86.3 

8(1.1 

.2 

85.2 

85.5 

— .3 

1st Ratoon* : 







90.(5 ** 

90.9” 

— .3** 

Sucrose iu Oimic % 






.11 

13 66 

1 3.75 

— .19 

.Plants : 

13.45 

13.47 

— .02 

13 76 

13.65 

1st Ratoons : 







15 Cl** 

15.92” 

-.28” 

Glucose Ratio, 



: 


6.43 

-.31 


7 54 

-.<52 

Plants : 

G68 

6.28 

.40 

6.12 

<5.92 

1st Ratoons : 

i 


» __ 



_ 

5.78** 

5 29” 

.49** 

Length per Stalk, ins. 
Plants : 

i 

i 73 

76 

i 

-3 

77 

80 

-3 

79 

83 

~4* 

Weight per Stalk, lb. 
Plants : 

1st Ratoons : 

i 2.10 

2 04 

.06 

! . 

2.31 

— 

2.57 

1.77” 

2.45 

1 .79** 

.12 

—.02** 


It will be seen that in neither crop had the single and double planting any 
statistically significant differential effects on the juice purity, the sucrose 
content of the cane, the glucose ratio or the weight per stalk. In the case of' 
length per stalk of the plant canes, the double planting tended to produce longer 
first and second order stalks, and in the late stalks the difference in favour of 
double planting was statistically significant. 

Summary. 

A comparison of single versus double planting was made with P.O.J.2878 
on acid silt overlying alkaline silt subsoil on the low-lying coastal belt of British 
Guiana. It was found that: 

1. In plant canes, double planting produced significantly more shoots per 
acre in the first five weeks and the second five weeks; 

__ 

“•Difference Significant. 

••The stalks of the first ratoon population were not separated as regards order of appearance. 

The data presented under ' late shoots ' for this crop are for all nullable qjjalks of the plots. 



DOUBLE VERSUS SINGLE PLANTING OP SUGAR CANE. 95 

2. At harvest double planting yielded significantly more millable stalks 
both in plants and ratoons; 

8. In the plant canes, mortality was higher among the double-planted than 
among the single-planted population, but insufficiently so to affect the 
great initial advantage of the former since it used up just less than 
half of it; 

4. Two-thirds of the first order (0 — 5 weeks) and a like number of the 
second order (6 — 10 weeks) shoots perished before the plant cane 
harvest and the two groups together formed only 30 to 36 per cent, of 
the whole harvest; 

6. Double planting, using less than two tons of extra planting material 
per acre, gave a significant increase of 12.98 per cent, in the yield of 
plant cane and 12.00 per cent, in the yield of first ratoon cane (a 
further advantage is a much better stand at the start and the almost 
total elimination of the expense of supplying blanks) ; 

6. No significant differences were observed between the weights of cane 
per stalk, the sucrose contents of the cane, the juice purities or the 
glucose ratios from single as against double planting, but the latter 
produced significantly longer late (after 10 weeks) stalks as plants. 



Catalogue of the lepidoptera rhopalocera 

(BUTTERFLIES) OF BRITISH GUI AN A— ( Contd.) 

BY 

ARTHUR HALL, F.R.Ent.S. 

145. PYRAMEIS CARDUI. 

Papilio cardui, Linnaeus, Faun. Snec. p. 276, n. 1054 (1761).' 

I took this cosmopolitan and migratory species at Bartica but it is at 
present a rarity in South America. 

146. PYRAMEIS MYRINNA. 

P. viyrinna, Doubleday, Gen. Diurn. Lcp. p. 203, n. 9 ("849). 

In the British Museum from Mt. Roraima. 

147. Precis lavinia. 

Papilio lavinia, Cramer, Pap. I, t. 21, C, D (1775). 

Generally distributed and common in open weedy places. It is very 
variable and a number of forms of no local constancy have been named. The 
form most prevalent in British Guiana, at any rate near Georgetown, is evarete 
Cramer which has no blue gloss on the hind wings. 

148. ANARTIA JATROrHAE. 

Papilio jatrophac, Linnaeus, Mus. Ulr. p. 269 (1764). 

One of the commonest butterflies nearly everywhere, preferring dry spots 
and open fields. Although so abundant nothing seems to be known of its 
early stages. 

149. Anartia AMATHEA. 

Papilio amathea, Linnaeus, Syst. Nat. I, p. 478, n. 118 (1758). 
Generally distributed and common. Unlike A. jatrophac it is partial to 
damp places such as the borders of trenches by the roadside. 

150. Eunica sophonisba. 

Papilio sopkonisba, Cramer, Pap. Ex. IV, t. 295, A, B (1782). 
Demerara River ; Tumatumari ; Potaro Road ; Barima River. Always rare 
and solitary. I have specimens dated March, July and August. 

151. Eunica amelia. 

Papilio amelia, Cramer, Pap. Ex. II, t. 136, B, C (1779). 

Singly from the Mazaruni and Potaro Rivers but always very scarce. 

152. Eunica viola. 

E. viola, Bates, Journ. Ent. II, p. 199, n. 34, t. 9, f. 4 (1864). 
Carimang River. Also a female in my collection from “ British Guiana ” 
collected by R. Haensch. 

153. Eunica orphise. 

® Papilio orphise, Cramer, Pap. Ex. I, t. 42, E, F (1776). 

A female from Omai in the British Museum; Berbice River (Coll. Ent. 

Div.) 



CATALOGUE OF THE LEP1DOPTERA RHOPALOCERA OF BRITISH GUIANA. 97 

154. Eunica ANNA. 

Papilio anna, Cramer, Pap. Ex. Ill, t. 281, A, B (1782). 

I have a single female of this species from Friendship on the Berbice River 
(H. C. Patoir). 

155. Eunica moninia. 

Papilio moninia, Cramer, Pap. Ex. IV, t. 387, F, G (1782). 

In the British Museum from Demerara. 

156. Eunica malvina. 

E. malvina, Bates, Journ. Ent. II, p. 195, n. 21, t. 9, f. 2, 2a (1864). 
Omai; Carimang River. 

157. PERIA lamis. 

Papilio lamia, Cramer, Pap. Ex. Ill, t. 238, E (1782). 

Bartica; Carimang River. Rather rare. 

158. Temeris laothoe. 

Papilio laothoe, Cramer, Pap. Ex. II, t. 132, A, B (1779). 

Demerara River; Friendship on the Berbice; Bartica; Omai; Kaieteur 
Falls; Mabaruma. Not very common although widely distributed. 

159. Catonephele acontius. 

Papilio acontius, Linnaeus, Mant. Plant, p. 537 (1771). 

Bartica; Kaieteur Falls; Mabaruma. Not rare in forest districts. 

160. Catonephele numilia. 

Papilio numilia, Cramer, Pap. Ex. II, t. 81, E, F (1779). 

A female from “ British Guiana ” in the British Museum. 

161. Ness vea obrinus. 

Papilio obrinus, Linnaeus, Syst. Nat. I, p. 470, n. 78 (1758). 
Demerara River; Parika; Berbice. Rather common at Parika from 
December to February, flying in deep shade but settling on leaves where a spot 
of sunshine breaks through. 

162. Nessaea batesii. 

Epicalia batesii, Felder, Wien. Ent. Mon. IV, p. 237, t. 3, f. 3, (1860). 
Demerara; Carimang River, Kuturi Sources. Much rarer than the preced- 
ing species. 

163. DYNAMINE ATHEMON. 

Papilio athemon, Linnaeus, Syst. Nat. I, p. 484, n. 157 (1758). 
Demerara River; Omai. 

164. Dynamine decima. 

Eubagis decima, Hewitson, Ex. Butt. I, Eubagis t. 1, f. 4-6 (1852). 

A feihale from the Carimang River has the white markings greatly reduced 
as compared with typical specimens from the Lower Amazon and may represent 
a new race. 

165. Dynamine onias. 

Eubagis onias, Hewitson, Ex. Butt. II, Eubagis t. 2, f. 13-15 (1857). 

A single female from “ British Guiana ” (Parish) in the British Museum. 



f)8 AhRictiLTijRA'L JOURNAL OP BRITISH GUIaNA. fX, & 

166. DYNAMINE RACIDULA. 

Eubagis racidula, Hewitson, Ex. Butt. I, Eubagis t. 1, f. 2, 3 (1852). 
Potaro River; Kaieteur Falls. 

167. Dynamine mylitta. 

Papilio mylitta, Cramer, Pap. Ex. Ill, t. 253, D, E (1782). 

The commonest species of the genus. Parika; Omai; Quonga. Probably 
to be found in most forest localities. 

168. Callicore clymena. 

Papilio clymena, Cramer, Pap. Ex. I, t. 24, E, F (1775). 

Quonga; Mabaruma; Mt. Roraima; Kuturi River; Upper Corentyne. 
Apparently rare in the Guianas although often abundant in other parts of South 
America. 

169. Catagramma IDAS. 

Papilio idas, Miiller, Natursystem, I, p. 633, t. 19, f. 11 (1774). 

One of the rarest butterflies of the Colony. There is a damaged female 
in the Georgetown Museum and 1 have seen two or three specimens from British 
Guiana but none with any definite localities. Further information about the 
species would be welcome. Two females from Demerara (C as tell) in the 
British Museum. 

170. Catagramma astarte. 

Papilio astarte, Cramer, Pap. Ex. Ill, t. 256, C, D (1782). 

A male in the British Museum from Friendship, Berbice River, and a 
female from “ British Guiana ”. 

171. Catagramma cynosura amazona. 

C. amazona, Bates, Jour. Enl. II. p. 209 n. 59, t. 10, f. 5, 5a (1864). 
A pair from the Kaieteur Falls (A. Hall) is the only record so far. 

172. Callithea leprieurii. 

C. leprieurn, Feisthamel, Rev. Zool. 1835, t. 122. 

Mr. W. J. Kaye saw this species near Bartica but was unable to capture it. 

173. Gynaecia dirce. 

Papilio dirce, Linnaeus, Syst. Nat. I, p. 477, n. 117 (1758). 

Common in many wooded places, settling on tree trunks with the wings 
closed. The early stages are wellknown, the larva feeding upon Cassia. 

174. Callizona acesta. 

Papilio acesta, Linnaeus, Syst. Nat. I, p. 479, n. 127 (1758). 

Annai; Berbice; Upper Real; Mabaruma. Similar in habits to Gynaecia 
dirce but much rarer. 

175. Haematera pyramus thysbe. 

H. thysbe, Doubleday & Hewitson, Gen. Diurn. Lep. t. 30, f. 4 (1848). 
In the British Museum from Quonga (H. Whitley). 

476. Ageronla februa. 

A. februa. Htibner, Samml. Ex. Schmett. (1816-24). 

Fairly common in wooded places. 



CATALOGUE OP THE LEPlDOPTERA RHOPALOCERA OP BRITISH GUIANA. <J9 

177. Ageronia IERONIA. 

. Papilio feronia, Linnaeus, Syst. Nat. I, p. 473, n. 05 (1758). 
Common and generally distributed. Like all species of the genus it settle* 
upon tree trunks with expanded wings. It makes a loud clicking sound when 
flying. 

178. Ageronia amphinome. 

Papilio amphinome, Linnaeus, Syst. Nat. I, (2', p. 779, n. 176 (1767). 
Not rare at Parika. 

179. Ageronia arinome. 

Peridromia arinome, Lucas, Rev. Zool. 1853, p. 312. 

Kuturi Sources (G. A. Hudson, Jan.-Feb. 1936) ; Demerara River; Groete 
Creek, R. Essequibo (G. Brinsley in Coll. Ent. Div. ) 

180. ECTIMA IONA. 

E. iona, Hewitson, Gen. Diurn. Lop., t. 42, f. 4 (1849). 

Annai; Potaro Road; Mabaruma. Always a rare species. Like the 
Ageroniae it settles on tree trunks with the w’ings expanded. 

181. Didonis bibus. 

Papilio biblis, Fabricius, Syst. Ent. p. 505, n. 261 (1775). 

Omai. Apparently rare in the Guianas. 

182. CYSTINEURA CANA. 

C. cana, Erichson, Schomb. Reisen III. p. 599 (1818). 

Annai; Quonga. 

183. Vila emilia. 

Papilio emilia, Cramer, Pap. Ex. Ill, t. 223, E, F (1782). 

King Frederick William Falls on the Corentyne (G. A. Hudson). 

184. Pyrrhogyra neaerea. 

Papilio neaetea, Linnaeus, Syst. Nat. I, p. 479, n. 126 (1758). 

Demerara River; Parika; Mabaruma (llall) in Coll. Ent. Div. In the form 
rcducta Hall from Parika (and French Guiana) the white bands are only half 
the normal width and ab. mclunotica Talbot is a unique abberration from British 
Guiana having the bands nearly obsolete. 

185. Pyrrhogyra crameri. 

P. crameri, Aurivillius, Kong. Svensk. Vet. Akad. Handl. IX, p. 98. 
Parika; Mabaruma. Not uncommon where found. 

186. Pyrrhogyra stratonicus. 

P. stratonicus, Fruhstorfer, Stett. Ent. Zcit. 1908, p. 36. 

I took a female of this species at Mabaruma in January 1930. As the 
only other known specimens have come from the Peru-Bolivian frontier its 
existence in British Guiana is a little surprising. . 

187. MEGALURA CHIRON. 

Papilio chiron, Fabricius, Syst. Ent. p. 452, n. 40 (1775). 

Upper Corentyne River (G. A. Hudson) ; “ British Guiana” in the British 
Museum. An abundant species in most parts of South America. 



AGRICULTURAL JOURNAL OP BRITISH GUIANA. 


tx. 2. 


100 


188. Megalura orsilochus. 

Papilio orsilochus, Fabricius, Gen. Ins. p. 252 (1777). 

Annai; Carimang River; Kaieteur Falls; Mabaruma. A very graceful 
species on the wing and never common. 

189. Megalura peleus. 

Papilio peleus, Sulzer, Gesch. Ins., t. 13, f. 4 (1776). 

Berbice. 

190. Hypolimnas misippus. 

Papilio misippus, Linnaeus, Mus. Ulr. p. 264 (1764). 

This East Indian species is a recent introduction into South America. It 
is to be found at Parika, Mabaruma and other places in the Colony. 

191. Victorina steneles. 

Papilio steneles, Linnaeus, Syst. Nat. I, p. 465, n. 124 (1758). 
Generally common and often abundant. 

192. Adelpha mesentina. 

Papilio mesentina, Cramer, Pap. Ex. II, t. 162, B, C (1779). 

Annai. 

I 

193. Adelpha tizona kayei. 

A, tizona kayei subsp. nov. 

Description. — Differs from all the described forms of A. tizona Feld. In 
the fore wings having three large subapical spots completely united with one 
another and with the oblique discal band, giving the latter the appearance of 
being forked. It has a superficial resemblance to A. ximena Feld. Potaro 
River. Type, a female in the collection of W. J. Kaye. 

194. Adelpha cocala. 

Papilio cocala, Cramer, Pap. Ex. Ill, t. 242, F, G. (1782). 

Demerara River; Annai; Omai; Carimang River; Mabaruma. 

195. Adelpha pseudococala. 

A. pseudococala, Hall, Nov. Zool. XXXIX, p. 10 (1933). 

Mabaruma; Kaieteur Falls. This species is difficult to distinguish from 
A. cocala but the Rev. Miles Moss has bred it at Para from totally different 
larvae and pupae. 

196. Adelpha erotia. 

Heterochroa erotia, Hewitson, Ann. Mag. Nat. Hist. XX, p. 269, t. 20, 
f. 3 (1847). 

I took a single very typical specimen at Mabaruma. 

197. Adelpha thesprotia. 

Heterochroa thesprotia, Felder, Reise Nov. Lep. Ill, p. 419, n. 653 
(1867). 

Berbice; Takutu; Oronoque-New River confluence (G. A. Hudson). 

198. Adelpha delphicola. 

A. delphicola, Fruhstorfer, Koch-Grunberg’s Reise II, p. 348. 

A specimen in my collection from Friendship on the Berbice River (H. C. 
Patoir). 



CATALOGUE OF THE LEPJDOPTERA RHOPALOCERA OF BRITISH GUIANA. 101 


199. Adelpha PHLIASSA. 

Nympkalis phlia&sa, Godart, Enc. Meth. IX, p. 373, n. 78 (1823). 
Annai; Berbice; Ida Sabina. 

200. Adelpha cytherea. 

Papilio cytherea, Linnaeus, Syst. Nat. I, p. 481, n. 139 (1758). 

The commonest species of the genus, usually in damp spots near second 
growth forest. 

201. Adelpha iphiclus. 

Papilio iphiclus, Linnaeus, Syst. Nat. I, p. 486, n. 172 (1758). 

Demerara River, Mabaruma. 

202. Adelpha melona. 

Heterochroa melona, Hewitson, Ann. Mag. Nat. Hist. XX, p. 258, t. 20, 
f. 2 (1847). 

Bartica; Mabaruma; Carimang River. A fairly common species in forests. 

203. Adelpha serpa. 

Heterochroa set pa, Boisduval, Spec. Gen. I, t. 8, f. 4 (1836). 

In the British Museum from the Carimang River. 

204. Adelpha paraena. 

Heterochroa paraena, Bates, Journ. Ent. II, p. 331, n. 167 (1865). 

A female in my collection from "British Guiana” (Parish). 

205. Chlorippe agathina. 

Papilio agathina, Cramer, Pap. Ex. II, t. 167, E, F (1782). 

Qnonga; Omai; King Frederick William Falls; Upper Corentyne. 

206. Historis OD1US. 

Papilio odius, Fabricius, Syst. Ent. p. 457, n. 60 (1775). 

Parika; Omai. Not uncommon. 

207. COEA ACHERONTA. 

Papilio acheronta, Fabricius, Syst. Ent. p. 501, n. 249 (1775''. 

Taken by J. G. Myers on the Rupununi Savannahs (Nov. 1933). 

208. Prepona demophon. 

Papilio demophon, Linnaeus, ‘Syst. Nat. I, p. 464, n. 36 (175P). 

Omai; Parika; Bartica, Mabaruma; Berbice (Coll. Ent. Div.) Fairly 
common and easily attracted to sugar on tree trunks. 

209. Prepona meander. 

Papilio meander, Cramer, Pap. Ex. I, t. 12, A, B (1775). 

Carimang River. 

210. Prepona pheridamas. . 

Papilio pkeridamas, Cramer, Pap. Ex. II, t. 158, A, B (1779). 

In the British Museum from Omai. 

211. Prepona antimache. 

Morpho antimache, Hiibner, Verz. Bek. Schmett. p. 49 n. 458 (1816). 
There are Specimens in the Georgetown Museum without definite locality. 



102 AGRICULTURAL JOURNAL OP BRITISH GUIANA. [X, 2. 

212. PREPONA DEXAMENES. 

P, dexamenes, Hoppfer, Stett. Ent. Zeit. 1874, p. 852, n. 64. 

A male from Demerara in the British Museum. 

213. Prepona omphale. 

Morpho omphale, Hiibner, Verz. bek. Schmett. p. 49, n. 454 1816) . 
Represented in the Georgetown Museum but with no indication as to 
whence the specimens came. There is no reason, however, to doubt its 
existence in the Colony. 

214. AGRIAS CLAUDIA. 

Papilio claudia, Schulz, Naturf. IX, p. 100, t. 2 (1776). 

This fine species is extremely rare and its headquarters in British Guiana 
are not definitely known. There are two or three specimens in the Georgetown 
Museum believed to have come from the Demerara River or Berbice and a dark 
aberration called info mils Fruhstorfer is said to have come from 
New Amsterdam but I have not seen an authentic British Guiana specimen 
in any English collection. 

215. Megistanis baeotus. ' 

M. baeotus, Doubleday & Hewitson, Gen. Diurn. Lop. t. 48, f. 2 (1850). 
Upper Kuturi River (G. A. Hudson). 

216. Megistants japetus. 

M. japetus, Standinger, Ex. Tagl. I, p. 174, t. 60 (1888). 

Oronoque River, near the Brazilian frontier. The hitherto undescribed 
female of this species has the bands of the upperside yellow instead of blue. 

217. Anaea heue. 

Papilio helie, Linnaeus, Syst. Nat. I, p. 475, n. 103 (1758). 

Marudi Mountain, Rupununi District (L. H. J. Ashburner). Th' 0 
species is probably better known under the name of A. ryphea, Cramer. 

218. Anaea eribotes. 

Papilio eribotes, Fabricius, Syst. Fnt, p. 484, n. 183 (1775). 

Demerara River; Kaieteur Falls. 

219. Anaea leonida. 

Papilio leonida, Cramer, Pap. Ex. IV, t. 388, C, D (1782). 

An old specimen in my collection is labelled “ Georgetown ”. If this is 
correct it was probably collected before the bush had been cleared from the 
vicinity. It is a fairly well known species in Dutch and French Guiana. 

220. Anaea pithyusa morena. 

A. pithyusa morena Hall, “Entomologist” LXVIII, p. 224 (1935). 
Mabaruma; Kuturi River; Upper Corentyne. It is a little strange that 
nearly all the specimens of this race which come to hand are females whereas 
in the typical race from Central America the males are far more abundant. * 

221. Anaea glauce. 

Nymphalis glauce, Felder, Wien. Ent. Mon. VI, p. 119, n. 132 (1862). 
Kaieteur Falls. (March 1936, A. Hall). 



CATALOGUE OP THE LEPIDOPTERA RHOPALOCERA OF BRITISH GUIANA. 103 


222. Anaea MORVUS. 

Papilio morvus, Fabricius, Syst. Ent. p. 484, n. 184 (1775). 
Carimang River; Bartica; Mabaruma; Mt. Roraima. Usually the 
commonest species of the genus. 

223. Anaea rasilea. 

Papilio hasilca, Cramer, Pap. Ex. IV, t. 329, E, F. (1782). 

Kuturi Sources (G. A. Hudson, Jan.-Feb. 1936). 

224. Anaea odilia. 

Papilio odilia, Cramer, Pap. Ex. IV, t. 329, C, D (1782). 

In my collection from Friendship on the Berbice. 

225. Hypna clytemnestra. 

Papilio clytemnestra, Cramer, Pap. Ex. II, t. 137, A, B (1779). 

Annai; Takutu; Kaieteur Falls; Kuturi River. Most British Guiana 
specimens belong to the rare typical form in which the fore-wings have no 
subapical spots. 

226. Zaretes isidora. 

Papilio isidora, Cramer, Pap. Ex. Ill, t. 235, A, B, E, F (1782). 
Parika. As this is a common species in neighbouring countries it is 
probably to be found elsewhere if looked for. 

227. SfDERONE MARTHESIA. 

Papilio marthcsia, Cramer, Pap. Ex. II, t. 191, A, B (1779). 

Potaro River (coll. W. J. Kaye). The older name of this fine species is 
probably S. yalanthis Cramer but the figure of the latter is sufficiently poor 
to be a little doubtful. 

228. Protogonius iiippona. 

Papilio hippova, Fabricius, Gen. Ins. p. 265 (1775).' 

Omai, Berbice; Parika; Mabaruma. 

229. LlBYTHEA CAR1NENTA. 

Papilio carinenta, Cramer, Pap. Ex. IT, t. 108, E, F (1779). 

Potaro River <W. J. Kaye). This particular genus probably belongs to the 
Nymphalidae and not to the Erycinidae. 

l'a mil y ER Y C I N I DA E. 

One of the peculiarities of this family is that many species only occur 
singly. A specimen of a certain species may be taken at a particular spot 
and no others may be found there again for a long period. For this reason 
many of our records are taken from single specimens. A. few species 
are common and are notable for their habit of settling on the under surface 
of leaves with the wings expanded flat, so that they seem to suddenly 
disappear from the sight of the observer. 



AGRICULTURAL JOURNAL Of BRITISH GUIANA. IX, 2. 

Sub-family EUSELASIINAE. 

2S0. Euselasia uzita. 

Eurygona uzita, Hewitson, Ex. Butt. II, Eurygona t 2, f. 12, IS 
(1852'). 

Annai. Apparently locally common. 

231. Euselasia mys. 

Eurygona mys, Herrich-Schaeffer, Ex. Schmett. f. 37, 38 (1835). 
Quonga; Mt. Roraima. 

232. Euselasia eucritus. 

Eurygona eucritus, Hewitson, Ex. Butt. II, Eurygona t. 2, f. 14-16 
(1852). 

Carimang River. 

233. Euselasia zena. 

Eurygona zena, Hewitson, Ex.